@article{KarppanenSirenEskeliKaivosoja1979, author = {Karppanen, H. and Sir{\´e}n, Anna-Leena and Eskeli-Kaivosoja, Alice}, title = {Central cardiovascular and thermal effects of Prostaglandin F2α in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47955}, year = {1979}, abstract = {Administration of PGF 2IX (0.2-6.4 J.lg) into the lateral cerebral ventricle (i.c.v.) induced dosedependent increases in blood pressure , heart rate and body temperature in urethane-anaesthetised rats, but had no effect on these parameters when the same dose range was administered intravenously. Peripheral pretreatment with sodium meclofenamate (50 mg/kg s.c.) sltifted all the dose-response curves for PGF 2IX (i.c.v.) to the left, but indomethacin (50 mg/kg s.c.) did not significantly affect those changes. Central pretreatment with sodiurn meclofenamate or indomethacin (1.25 mg per rat i.c.v.) failed to modify significantly the effects of centrally administered PGF 2IX' The results support previous suggestions that PGF 2IX may participate in the central control of the cardiovascular and thermoregulatory systems, and also suggest that there may be differences in the sites and/or modes of action between sodiurn meclofenamate and indomethacin.}, subject = {Prostaglandine}, language = {en} } @article{SirenKarppanen1980, author = {Sir{\´e}n, Anna-Leena and Karppanen, H.}, title = {Influence of analgesic antipyretics on the central cardiovascular effects of clonidine in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-48640}, year = {1980}, abstract = {No abstract available}, subject = {Prostaglandine}, language = {en} } @article{Siren1981, author = {Sir{\´e}n, Anna-Leena}, title = {Central cardiovascular and thermal effects of prostacyclin in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47943}, year = {1981}, abstract = {Prostacyclin (PGI2) induced a dose-dependent decrease in blood pressure with slight increases in heart rate and body temperature, when administered at the doses of 0.1-100 ~g into the lateral cerebral ventricle (i.c.v.) of the urethane-anaesthetised rat. When the same doses were administered intravenously, both the blood pressure and heart rate decreased. Central pretreatment wib~ sodiurn meclofenamate (1 mg/rat i.c.v.) antagonised the central hypotensive effect of PGI2 but i.c.v. pretreatrnent of the rats with indomethacin (1 mg/rat) failed to affect the PGI 2-induced hypotension. Central pretreatment with two histamine H2-receptor antagonists, cimetidine (500 ~g/rat i.c.v.) or metiamide (488 ~g/rat i.c.v.), antagonised the blood pressure lowering effect of 0.1 ~g dose of PGI2 but failed to affect the hypotension induced by higher PGI2 doses. Therefore the main central hypotensive effect of PGI2 seems not to be associated with the stimulation of histamine H2 -receptors in the brain. The hypotensive effect of i.c.v. administered PGI2 appears to be due to an action upon the central nervous system rather than to a leakage into the peripheral circulation. This assurnption is supported by the fact that sodiurn meclofenamate i.c.v. antagonised the effect of PGI 2. In addition, the chronotropic response to i.c.v. PGI2 was opposite to that induced by intravenous administration. The results also suggest that there may be differences in the mode of action between sodiurn meclofenamate and indomethacin.}, subject = {Prostaglandine}, language = {en} } @article{Siren1982, author = {Sir{\´e}n, Anna-Leena}, title = {Differences in central actions of arachidonic acid and prostaglandin F\(_{2\alpha}\) between spontaneously hypertensive and normotensive rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63324}, year = {1982}, abstract = {Prostag1andin F\(_{2\alpha}\) (PGF\(_{2\alpha}\)) is one of the most common metabo1ites of arachidonic acid (M) in rat brain. When administered intracerebroventricularly (i.c.v.) to rats, both AA and PGFal exert dose-related hypertensive, tachycardic and hyperthermic effects. Metabolie alterations in the endogenaus formation of some prostaglandins in the brain-stem of spontaneously hypertensive rats (SHR) have been reported. Therefore the central effects of AA and PGF \(_{2\alpha}\) on blood pressure, heart rate and body temperature were studied both in SHR and nonootensive Wistar rats (NR) under urethane-anaesthesia. The hypertensive effect of AA i.c.v. (0.01-100 \(\mu\)g/rat) was larger in magni tude in SHR than in NR, but there was no significant difference in the M-induced changes of heart rate and body temperature between the groups. Pretreatment of NR wi th soditm1 :meclofenamate (1 mg/rat i.c.v.) antagonised the central effects of M indicating that these effects are not due to M itself but to its conversion to prostaglandins. Unlike the effects of AA, the central hypertensive, tachycardic and hyperthennic responses to PGF\(_{2\alpha}\) (0.5-50 l-lg/rat i.c.v .) were significantly attenuated in SHR. The present results obtained with M are conpatible with the previous assumption that the synthesis of prostaglandins in the brain of SHR might differ from that in NR. The results also demonstrate that the central effects of PGF\(_{2\alpha}\) are reduced in SHR.}, subject = {Neurobiologie}, language = {en} } @article{Siren1982, author = {Sir{\´e}n, Anna-Leena}, title = {Central cardiovascular and thermal effects of Prostaglandin E2 in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47960}, year = {1982}, abstract = {Prostaglandin E2 (PGE2) increased the blood pressure, heart rate and body temperature, when administered at the doses ofO.OOI-IO,ug into the lateral cerebral ventricle (i.c.v.) of the urethane-anesthetised rat. The highest dose of 10 ,ug/rat induced a strong initial hypotensive effect. lntravenously (i.v.), PGE2 at the doses of 0.01-10 ,ug/rat caused a biphasic blood pressure response with dose-related initial decreases followed by slight increases in blood pressure. The heart rate and body temperature were slightly increased by i.v. administrations of PGE2 . The highest i.v. dose of 10 ,ug/rat initially decreased also the heart rate. Central pretreatment with indomethacin ( I mg/rat i.c.v.) partly antagonised all of the recorded central effects of PGE2 , while sodium meclofenamate (I mg/rat i.c. v.) abolished the hypertensive response to i.c. v. administered PGE2 but failed to significantly affect the PGE2-induced rises of heart rate and body temperature. The results support the previous suggestions that PGE2 may participate in the central cardiovascular and thermoregulatory contro!. The results also suggest that indomethacin and sodium meclofenamate antagonize the effects of exogenous prostaglandins. Since sodium meclofenamate, unlike indomethacin, affected preferentially the hypertensive response to centrally administered PGE2 , there may be differences in the sites and/or modes of action between these drugs.}, subject = {Physiologie}, language = {en} } @article{Siren1982, author = {Sir{\´e}n, Anna-Leena}, title = {Central cardiovascular and thermal effects of prostaglandin D2 in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-48658}, year = {1982}, abstract = {Prostaglandin D2 (PGD2) is the most common prostaglandin type of tile rat brain. Recently a neurornodulator role for PGD2 has been suggested. In the present work the central cardiovascular and thermal effects of PGDz were studied in urethane-anaesthetised rats. Mlen adrndnistered at the doses of 0.001-10 ~g/rat into the lateral cerebral ventricle(i.c.v.), PGD2 slightly increased the blood pressure, heart rate and body ternpera~ ure. The highest dose caused also an initial hypotensive effect. Upon lntravenous injections PGD2 (0.1-10 ~g/rat) initially decreased and then weakly increased the blood pressure but had only negligible effects on heart rate and body temperature. Central pretreatment with sodium meclofenamate or indomethacin (1 mg/rat i.c.v.) antagonised effectively all the recorded central effects of PGD2. The central cardiovascular and thermal effects of PGD2 were much weaker than those obtained earlier with other prostaglandins, such as PGF2alpha and PGE2.. Therefore, in spite of its abundance in the brain PGD2 may not be very important for the central cardiovascular and thermal regulation in the rat.}, subject = {Medizin}, language = {en} } @article{SirenPaakkari1984, author = {Sir{\´e}n, Anna-Leena and Paakkari, I.}, title = {Cardiovascular effects of TRH i.c.v. in conscious rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-49071}, year = {1984}, abstract = {In addition to the endocrine effects, the thyrotropin releasing hormone (TRH) is known to induce dose-dependent increases in blood pressure and heart rate after intracerebroventricular (i.c.v.) administration in urethane-anaesthetised rats (1, 2). The a~ of the present study was to investigate whether TRH has similar effects in conscious rats of various strains i.e. spontaneously hypertensive rats (SHR), normotensive Wistar-Kyoto (WKY) and Wistar (NR) rats.}, subject = {Medizin}, language = {en} } @article{SirenSvarstroemFraserPaakkari1985, author = {Sir{\´e}n, Anna-Leena and Svarstr{\"o}m-Fraser, M. and Paakkari, I.}, title = {Central cardiovascular effects of the endoperoxide analogue U-46619 i.c.v. in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-49064}, year = {1985}, abstract = {Thromboxanes are abundantly present in the rat brain but their possible physiological functions in the brain are not known. The prostaglandin endoperoxide analogue U-46619 is a selective agonist of TxA2 receptors in many peripheral tissues. In the present study the ·central cardiovascular and ventilatory effects of U-46619 were investigated in rats. In conscious spontaneously hypertensive rats (SHR) U-46619 (1-100 nmol/kg i.c.v.) induced a strong dose-related increase in blood pressure but had no significant effect on heart rate. In conscious normotensive rats (NR) neither blood pressure nor heart rate was significantly affected. Furthermore, U-46619 (0.1-100 nmol/kg i.c.v.) had no significant effect on blood pressure, heart rate or ventilation in urethane-anaesthetised NR . The results demonstrate an increased sensitivity of SHR to TxA2.}, subject = {Medizin}, language = {en} } @article{EimerlSirenFeuerstein1986, author = {Eimerl, J. and Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Systemic and regional hemodynamic effects of leukotrienes D\(_4\) and E\(_4\) in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63317}, year = {1986}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{PaakkariNurminenSiren1986, author = {Paakkari, I. and Nurminen, M-L. and Sir{\´e}n, Anna-Leena}, title = {Cardioventilatory effects of TRH in anesthetized rats: role of the brainstem}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63277}, year = {1986}, abstract = {Cardioventilator responses were studied in anaesthetized rats after injections of TRH into either the lateral (i.c.v. lat) or the fourth (i.c.v. IV) cerebral ventricles. TRH induced a morerapid hypertensive effect i.c.v. IV than i.c.v. lat. Blocking of the cerebral aqueduct abolished the hypertensive and tachypnoeic effects of TRH i.c.v. lat but not those of TRH i.c.v. IV. It is concluded that TRH increased blood pressure and ventilation rate via brain stem structures close to the fourtli ventricle.}, subject = {Neurobiologie}, language = {en} } @article{SirenPowellFeuerstein1986, author = {Sir{\´e}n, Anna-Leena and Powell, E. and Feuerstein, G.}, title = {Thyrotropin releasing hormone in hypovolemia: a hemodynamic evaluation in the rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63288}, year = {1986}, abstract = {ln the present study the effects of thyrotropin releasing hormone (TRH) and its stable analogue, CG3703, on cardiac output (thermodilution, Cardiomax) and regional blood flow (BF; directional pulsed Doppler technique) were investigated in hypovolemic hypotension in the rat. In urethan-anesthetized rats TRH (0.5 or 2 mg/ kg ia) or CG3703 (0.05 or 0.5 mg/kg ia) reversed the bleeding (27\% of the blood volume)-induced decreases in mean arterial ...}, subject = {Neurobiologie}, language = {en} } @article{SirenFeuerstein1986, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Effect of T-2 toxin on regional blood flow and vascular resistance in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63293}, year = {1986}, abstract = {The acute effect ofT-2 toxemia on local blood flow and vascular resistance in hindquarter. mesenteric. and renal vascular beds was continuously measured by the directional pulsed Doppler technique in conscious, male Sprague-Dawley rats. Intravenous injection ofT-2 toxin (I mg/kg) in the conscious rat reduced blood flow and increased vascular resistance in all blood vessels studied but had no significant effect on mean arterial pressure or heart rate. The blood flow in hindquarters gradually decreased to a minimum of -77 ± 9\% (mean ±SE) 6 hr after the toxin injection. The hindquarter vascular resistance concomitantly increased to a maximum value of + 323 ± 69\% above thc resistance before toxin administration. Mesenteric and renal blood flow initially increased (slightly) and then gradually decreased. The maximum drop of blood flow, -90 ± 13\% and -76 ± 13\% for the mesenteric and renal vascular beds, respectively, was achieved 4 hr after T-2 toxin injection and the blood flow values remained low for up to 6 hr. Simultaneously with the impairment of}, subject = {Neurobiologie}, language = {en} } @article{SirenFeuersteinLabrooetal.1986, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G. and Labroo, V. M. and Coleen, L. A. and Lozovsky, D.}, title = {Effect of thyrotropin releasing hormone and some of its histidine analogs on the cardiovascular system and prolactin release in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63307}, year = {1986}, abstract = {The cardiovascular and endocrine activity of three analogs of thyrotropin releasing hor.mone (TRH), 4-nitro-imidazole TRH (4-nitroTRH), 2-trifluoro-methyl-imidazole TRH (2-TFM-TRH) and 4-trifluoromethyl- imidazole TRH (4-TFM-TRH), was compared to TRH in conscious rats. Injection of TRH or the three analogs (1 mg/kg or 5 mg/kg) into the arterial line induced increases in mean arterial pressure, pulse pressure and heart rate and raised plasma prolactin (PRL). None of the analogs were more potent than TRH in inducing cardiovascular changes. The 4-TFM-TRH was significantly less potent than the 2-TFM-TRH in increasing blood pressure, while the nitro-TRH was more potent than the 2-TFM-TRH in producing tachycardia. TRH induced a two-fold increase in PRL at the 5 mg/kg dose, while both the fluorinated analogs elici ted a 4 to 5 fold increase in PRL at the higher dose. The present results suggest that the receptors for TRH-elicited PRL release differ from TRH-receptors involved in its cardiovascular actions.}, subject = {Neurobiologie}, language = {en} } @article{FeuersteinSiren1986, author = {Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {Effect of naloxone and morphine on survival of conscious rats after hemorrhage}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-48669}, year = {1986}, abstract = {The endogenous opioid system has been reported to depress the cardiovascular system during shock states, since naloxone, a potent opiate antagonist, enhances recovery of hemodynamic variables in various shock states. However, the effect of naloxone on long-term survival of experimental animals exposed to hypovolemic hypotension is not clear. The present studies tested the capacity of various doses of naloxone to protect conscious rats from mortality following various bleeding paradigms. In addition, the effect of morphine on survival of rats exposed to hemorrhage was also examined. In the six different experimental protocols tested, naloxone treatments failed to improve short- or long-term survival; in fact, naloxone treatment reduced short-term survival in two of the experimental protocols. Morphine injection, however, enhanced the mortality of rats exposed to hemorrhage in a dose-dependent manner. It is concluded that while opiates administered exogenously decrease survival after acute bleeding, naloxone has no protective action in such states and, like morphine, it may decrease survival in some situations.}, subject = {Medizin}, language = {en} } @article{FeuersteinLeaderSirenetal.1987, author = {Feuerstein, G. and Leader, P. and Sir{\´e}n, Anna-Leena and Braquet, P.}, title = {Protective effect of PAF-acether antagonist, BN 52021, in trichothecen toxicosis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63244}, year = {1987}, abstract = {Trichothecenes are mycotoxins which produce Iethai toxicosis in humans and animals, yet no adequate therapeutic regimen has been developed. This study provides evidence that the selective platelet activating factor (PAF) antagonist, BN 52021 (5-15 mg/kg i.v.) can prolong the survival of conscious rats exposed to a highly Iethai T -2 toxicosis. These data also suggest that P AF is an important mediator of this unique toxicosis.}, subject = {Neurobiologie}, language = {en} } @article{LabrooCohenLozovskyetal.1987, author = {Labroo, V. M. and Cohen, L. A. and Lozovsky, D. and Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Dissociation of the cardiovascular and prolactin-releasing activities of TRH by histidine replacement}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63253}, year = {1987}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @misc{FeuersteinSiren1987, author = {Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {Opioid peptides: A role in hypertension? [Brief Review]}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63262}, year = {1987}, abstract = {This review is an attempt to highlight evidence that may implicate the endogenaus opioid system in the pathogenesis of hypertension in humans. The evidence raised includes biochemical, physiological, pharmacological, and behavioral studies con~ucted in in vitro andin vivo systems, experimental models of hypertension, and hornans with essential hypertension. While the compelling biochemical and pharmacological evidence in experimental animals clearly shows the presence of opioid peptides and their receptors in strategic sites of cardiovascular control and potent cardiovascular response to opioid peptides, opioid antagonists show no consistent blockade or reversal of hypertension in experimental animals or humans. One possible explanation for this phenomenon could be the vast redundancy in systems regulating blood pressure (i.e., the blockade ofone system stillleaves many other systerils fully able to rapidly offset the eliminated system). Regarding the opioid system, the situation is much more complex, since some opioid receptors (\(\mu\)-type) niediate pressor responses, while other receptors (\(\kappa\)type) mediate depressor responses. Therefore, nonselective opioid receptor antagonists (e.g., naloxone), which block both types ofreceptors, can be devoid ofany cardiovascular activity, while a selective \(\mu\)-receptor antagonist or a selective arid potent \(\kappa\)-receptor agonist may produce the desired antihypertensive elfect. A combination of both actions (i.e., a drug that is both \(\mu\)antagonist and a \(\kappa\)antagonist) might be even more advantageous. Until such compounds are developed, this hypothesis will be hard to prove.}, subject = {Neurobiologie}, language = {en} } @article{FeuersteinSiren1987, author = {Feuerstein, Giora and Sir{\´e}n, Anna-Leena}, title = {The Opioid System in cardiac and vascular regulation of normal and hypertensive states}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47418}, year = {1987}, abstract = {The endogenous opioid system includes three major families of peptides: dynorphins (derived from pre-proenkephalin B), endorphins (derived from pre-proopiomelanocortin), and enkephalins (derived from pre-proenkephalin A). Multiple species of opioid peptides are derived from these major precursors and many of them possess potent cardiovascular properties. Opioid peptides and opioid receptors, of which multiple forms have been defined, are present in the central nervous system and peripheral neural elements. In the central nervous system, opioid peptides and receptors are found in forebrain and hindbrain nuclei involved in baroregulation, sympathoadrenal activation, and several other vital autonomic functions. In the periphery, opioid peptides are found in autonomic ganglia, adrenal gland, heart, and other organs; multiple opioid receptors are also found in vascular tissue, heart, and kidneys. Although little is known to date on the regulatory mechanisms of the opioid system in normal cardiovascular states, it became clear that cardiovascular stress situations substantially modify the activity of the endogenous opioid system. The purpose of this review is to clarify the sites of interaction of the opioid system with all major components of the cardiovascular system and indicate the potential role of this system in the ontogenesis of cardiac malfunction, vascular diseases, and hypertension.}, subject = {Medizin}, language = {en} } @article{FeuersteinSiren1987, author = {Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {Cardiovascular effects of enkephalins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-49048}, year = {1987}, abstract = {Enkephalins and their receptors are found in neurons and nerve terminals known to be involved in central cardiovascular control as well as the peripheral sympathetic and parasympathetic systems. Enkephalins and opioid receptors were also iden tified in the heart, kidneys, and blood vessels. The enkephalins interact with several specific receptors, of which p, 0, and K have been best characterized. Enkephalins administered to humans or animals produce cardiovascular effects which depend on the spedes, route of administration, anesthesia, and the selectivity for receptor subtype. While little information exists on the role of enkephalins in normal cardiovascular control, current data suggest that enkephalins might have a role in cardiovascular stress responses such os in shock and trauma.}, subject = {Medizin}, language = {en} } @article{SirenFeuerstein1987, author = {Sir{\´e}n, Anna-Leena and Feuerstein, Giera}, title = {Central autonomic pharmacology of thyrotropin releasing hormone}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-49051}, year = {1987}, abstract = {Thyrotropin releasing hormone (TRH, I-pyroglutamyl-l-histidyl-l-prolinamide) was the fIrst hypothalamic releasing SUbstance to be isolated, chemically characterized and synthetized /1/. The studies to date have revealed that the thyrotropin release from the pituitary gland is only one of the numerous actions of TRH. In addition to its endocrine actions (TSH and prolactin release) this tripeptide has central nervous system actions totally unrelated to its effects on the hypothalamo-pituitary axis. This review aims to summarize the studies on the central nervous system' actions of TRH with special emphasis on the autonomic pharmacology of this peptide.}, subject = {Medizin}, language = {en} } @article{PaakkariSirenNurminenetal.1987, author = {Paakkari, I. and Sir{\´e}n, Anna-Leena and Nurminen, M.-L. and Svartstr{\"o}m-Fraser, M.}, title = {Injection of thyrotropin releasing hormone into the locus coeruleus increases blood pressure}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-72894}, year = {1987}, abstract = {Thyrotropin releasing hormone (TRH), 10 pmol kg-1 injected in the region of locus coeruleus, caused a rapid (within 1 min) rise of mean arterial pressure in the urethane- naesthetized rat. No clear-cut effects in heart rate or ventilation were observed. When TRH was injected into the lateral ventricle, a dose more than 10-fold higher was required to achieve a comparable rise in arterial pressure. It is concluded that TRH may have a physiological rote in centrat cardiovascular regulation.}, subject = {Thyreotropin-Releasinghormon}, language = {en} } @article{FeuersteinLettsSiren1988, author = {Feuerstein, G. and Letts, G. and Sir{\´e}n, Anna-Leena}, title = {N-Ac-Leukotriene E\(_4\): Unique vascular activity in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63171}, year = {1988}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{SirenLakeFeuerstein1988, author = {Sir{\´e}n, Anna-Leena and Lake, C. R. and Feuerstein, G.}, title = {Hemodynamic and neural mechanisms of action of thyrotropin releasing hormone in the rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63183}, year = {1988}, abstract = {Tbe mechanisms mediating the etl'ects ofthyrotropin-releasing hormone (TRH) on the cardiovascular system were studied in the conscious rat. Intracerebroventricolar (i.c. v.) injection of TRH (8 pmol-80 nmollkg) induced dose-dependent lncreases in mean arterial pressure, heart rate, and cardiac index. Rindquarter blood Oow increased due to vasodilation, while an lncrease in renal and mesenteric vascular resistance caused a decrease in blood Oow in the respective organs. The plasma Ievels of norepinephrine a~d epinephrine were increased by TRH, while there was no change in plasma renin activity or vasopressin. Tbe cardiovascular actions of i.c. v. TRH were not in.fluenced by blockade of the renin-angiotensin system or vasopressin receptors. Tbe ganglion blocker chlorisondamine and the a 1- aod al-adrenoreceptor antagooist phentolamlne (2 mg/kg i.v.) abolished the increase in blood pressure and mesenteric vasoconstriction after i.c. v. TRH. Propranolol (2 mg/kg i. v.) blocked the TRH-ioduced increase in cardiac index, heart rate, and hindquarter blood flow. The hindquarter vasodllatlon lnduced by TRH was also blocked by the selective ß1-adrenocept9r antagonist ICI 188,551 (1 or 2 mg/kg i.v.), while tbe ,8,-adrenoceptor blocker practolol (10 mg/kg i.v.) had no eft'ect on the hindquarter vasodiJation produced by TRH but totally blocked the increase in cardiac Index. In adrenal demedullated rats, the systemic hemodynamic eft'ects ofi.c. v. TRH were dimlnished along with the decrease in renal blood flow and lncrease in renal vascular resistance; however, the iocrease in hfndquarter blood flow was attenuated only in adrenal demedullated rats pretreated with the sympathetlc blocker bretylium. The renal vasoconstriction induced by i.c. v. TRH was not abolished by renal denervation. In sinoaortic debufl'ered rats, the pressor, tachycardic, and mesenteric vasoconstrictor responses to centrally administered TRH were significantly potentiated. Taken together, these data soggest that the putative rieurotransmitter TRH may play a role in central regulation of cardiac functions and organ blood flow distribution through both tbe sympathetic nerves and the adrenal medulla. A pivotal roJe for ß1-adrenoceptors in mediation ofhindquarter vasodilation ls also demonstrated.}, subject = {Neurobiologie}, language = {en} } @article{SirenLettsFeuerstein1988, author = {Sir{\´e}n, Anna-Leena and Letts, G. and Feuerstein, G.}, title = {N-Acetyl-leukotriene E\(_4\) is a potent constrictor of rat mesenteric vessels}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63196}, year = {1988}, abstract = {N-Acetyl-leukotriene E\(_4\) administered to conscious freely moving rats produced a dose-dependent vasoconstriction in the mesenteric vessels which led to profound reduction of blood flow to the gut. Renal and hindquarter blood flow and vascular resistance were not affected even by high doses of N-acetyl-leukotriene E\(_4\) . N-Acetyl-leukotriene E\(_4\) was 10-fold more potent than the thromboxane analog U-46619 and 1000-fold more potent than prostaglandin F\(_{2a}\) but 2-5-fold less potent than leukotriene D\(_4\)/E\(_4\) to induce mesenteric vasoconstriction. These data indicatc that N-acetylleukotriene E\(_4\) is a biologically active metabolite of peptide leukotrienes, and might play a role in cardiovascular derangements mediated by leukotrienes.}, subject = {Neurobiologie}, language = {en} } @article{FeuersteinSiren1988, author = {Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {Mesenteric vascular responses to i.v. administration of lipoxin A\(_4\) and lipoxin B\(_4\) in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63200}, year = {1988}, abstract = {Lipoxin A (LXA\(_4\)) and lipoxin B\(_4\)(LXB\(_4\)) are newly discovered lipoxygenase-interacting products of leukocytes which might have a role in cardiovascular events associated with anaphylaxis. We have tested this possibility by systemic administration of both LXA\(_4\) and LXB\(_4\) to the conscious rat while monitaring systemic and regional hemodynamic changes. LXA\(_4\) and' LXB\(_4\) (l-100 pg/kg) produced dose-dependent constriction of the mesenteric vessels, up to + 123±23\% and +50±9\% for LXA\(_4\)/B\(_4\) , respectively. Dose-related changes were not observed in arterial blood pressure, heart rate, renal (LXB\(_4\)) and hindquarter blood ftow. We suggest that LXA\(_4\) and LXB\(_4\) might affect selective vascular beds, such as the mesenteric vessels, and contribute to variations in blood flow in specific pathophysiological states.}, subject = {Neurobiologie}, language = {en} } @article{Siren1988, author = {Sir{\´e}n, Anna-Leena}, title = {Cardiovascular pharmacology of thyrotropin releasing hormone}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63214}, year = {1988}, subject = {Neurobiologie}, language = {en} } @article{FeuersteinSiren1988, author = {Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {Hypothalamic µ-receptors in the cardiovascular control: a review}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63228}, year = {1988}, abstract = {The endogenous opioid system includes three major families of peptides [22): dynorphins (derived from pre-proenkephalin B); endorphins (derived from pre-proopiomelanocortin) and enkephalins (derived from pre-proenkephalin A). Multiple species of opioid peptides are derived from these major precursors and many of them possess potent cardiovascular properties. Multiple forms of opioid receptors have been defined in the central nervous system. Although the relationship of these receptors to the multiple actions of the opioid systems is not weil understood, some predications can be made: in vitro the dynorphin-related peptidesbind preferentially to kappa-opioid receptors; the enkephalins bind preferentially to delta and JL-opioid receptors and while beta-endorphin binds to mu- and delta-, but not to kappa-opioid receptors. While littleis known on the roJe ofthe opioid system in normal cardiovascular regulation, it has become clear that cardiovascular stress situations substantially modify the activity ofthe endogenous opioid system. This review focuses on the mu-opioid system in the hypothalamus with special emphasis on its potential roJe in cardiovascular control of both normal and pathophysiologic states.}, subject = {Neurobiologie}, language = {en} } @article{SirenFeuerstein1988, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Cardiovascular effects of rat calcitonin gene-related peptide in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63236}, year = {1988}, subject = {Neurobiologie}, language = {en} } @article{HallenbeckDutkaKochaneketal.1988, author = {Hallenbeck, JM and Dutka, AJ and Kochanek, PM and Sir{\´e}n, Anna-Leena and Pezeskpour, GH and Feuerstein, G.}, title = {Stroke risk factors prepare rat brainstem tissues for a modified localized Shwartzman reaction}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47971}, year = {1988}, abstract = {Stroke risk factors such as hypertension, diabetes, advanced age, and genetic predisposition to stroke were demonstrated to prepare rat brainstem tissues for a modified local Shwartzman reaction. A single intracisternal injection of endotoxin provoked the reaction, and affected rats manifested neurologie deficits accompanied by pathologie lesions. Brainstem infarcts developed in only a small proportion of rats without recognized risk factors after intracisternal injection of endotoxin. Thus, stroke risk factors, whieh are ordinarily regarded as operating through acceleration of atherosclerosis, may predispose to brain ischemia by local effects on brain mierocirculation such as those thought to underlie preparation of a tissue for the local Shwartzman reaction.}, subject = {Gehirn}, language = {en} } @article{SirenFeuerstein1989, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Effect of PAF and BN 52021 on cardiac function and regional blood flow in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63145}, year = {1989}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{SirenFeuerstein1989, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Thyrotropin releasing hormone-induced hindquarter vasodilation is mediated by \(\beta _2\)-adrenoceptors}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63155}, year = {1989}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{SirenFeuerstein1989, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Hemodynamic effects of endothelin after systemic and central nervous System administration in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63165}, year = {1989}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{SirenPaakkariGoldsteinetal.1989, author = {Sir{\´e}n, Anna-Leena and Paakkari, P. and Goldstein, D. S. and Feuerstein, G.}, title = {Mechanism of central hemodynamic and sympathetic regulation by µ-opioid receptors: Effects of dermorphin in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63123}, year = {1989}, abstract = {The effects of i.c.v. administered dermorphin, a highly selective \(\mu\)-opioid agonist, on cardiac function and renal, mesenteric and hindquarter blood ftow were studied in conscious rats. Core temperature, blood gases, arterial plasma levels of norepinephrine, epinephrine, dopamine, 3,4-dihydroxyphenylalanine and dihydroxyphenylacetic acid (DOPAC) also were examined. Cardiac output was rneasured using a thermodilution technique and regional blood ftows using directional pulsed Doppler velocimetry. Dermorphin, at doses of 0.1-100 nmol/kg, increased blood pressure and hindquarter blood flow, renal and mesenteric resistance, and core temperature. Higher doses (1-5 \(\mu\)mol/kg) caused respiratory depression, acidosis, and shock despite profaund sympatho-adrenomedullary stimulation. Circulating Ieveis of catecholamines were significantly increased at the dermorphin doses of 0.1-1 00 nmol/kg. At the 100 nmol/kg dose, plasma levels of epinephrine, norepinephrine, the dopamine metabellte dihydroxyphenylacetic acid and the catecholamine precursor 3,4,-dihydroxyphenylalanine were increased by 2-15-fold. The data indicate that mu opioid receptor Stimulation exerts potent effects on cardiorespiratory functions, activates the sympathoadrenomedullary system and produces a pattem of blood flow changes consistent with the stress-induced •detense· response (skeletal muscle vasodilation and splanchnic vasoconstriction). Excessive mu opioid receptor Stimulation Ieads to shock due to respiratory and hemodynamic collapse.}, subject = {Neurobiologie}, language = {en} } @article{SirenEimerlFeuerstein1989, author = {Sir{\´e}n, Anna-Leena and Eimerl, J. and Feuerstein, G.}, title = {L-649,923 : An antagonist of cardiac and vascular leukotriene D\(_4\) receptors}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63134}, year = {1989}, abstract = {The capacity of L-649,923-sodium ( ßS, -yR * )-4-(3-( 4-acetyl-3-hydroxy-2-propylphenoxy)propylthio)-- y-hydroxy-ß-methylbenzene butanoate-to block vascular receptors of leukotriene D\(_4\) ( L TD\(_4\)) was examined in the conscious rat. Hindquarter (HQ), renal, and mesenteric blood flow and vascular resistance were evaluated in the conscious rat chronically equipped with miniaturized Doppler probes for organ blood flow measurement by directional pulsed Doppler technique. In addition, cardiac outpul was measured by thermodilution technique in conscious rats equipped with minithermistors in the ascending aorta. Systemic hemodynamic variables. mean arterial pressure, and heart rate were monitored through femoral catheters. L TD\(_4\) (I or 10 \(\mu\)g/kg) produced a marked dose dependent increase in the mesenteric vascular resistance associated with a marked decrease in blood flow whereas no consistent effects were demonstrated in the renal circulation. L TD\(_4\) • at I \(\mu\)g/kg. increased the HQ blood flow whereas the higher dose of LTD\(_4\) produced a biphasic response: an early increase followed by a decrease in blood flow. Infusion of L TD\(_4\) • 3 \(\mu\)g/kg per min over 10 min decreased cardiac output and increased total peripheral resistance. L-649,923 (10 or 30 mg/kg, i.v.) effectively blocked the L TD4-induced mesenteric constriction and the second I phase of HQ vasoconstriction but did not modify the , LTD\(_4\) induced HQ vasodilation. L-649,923 also effectively attenuated the cardiac effects of LTD\(_4\) infusion. I These studies suggest that L-649,923 could preserve cardiac and vascular functions in pathologic states mediated by cysteinylleukotrienes, such as traumatic or endotoxin shock. Key Words: Leukotriene D4 -Cardiovascular system- Leukotriene antagonist- Mesenteric blood tlow-Renal blood flow-Hindquarter blood flowAnaphylaxis.}, subject = {Neurobiologie}, language = {en} } @article{FeuersteinSirenGoldsteinetal.1989, author = {Feuerstein, G. and Sir{\´e}n, Anna-Leena and Goldstein, DS and Johnson, AK and Zerbe, RL}, title = {The effect of morphine on the hemodynamic and neuroendocrine responses to hemorrhagic shock in conscious rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-49033}, year = {1989}, abstract = {We have previously reported that analgesic doses of morphine accelerate mortality of rats exposed to hemorrhage (Feuerstein and Siren: Circ Shock 19:293-300, 1986). To study the potential mechanisms involved in this phenomenon, rats were chronically implanted with catheters in the femoral vessels and morphine (1.5 or 5 mg/kg) was administered 30 min or 24 hr after bleeding (8.5 mll300 g over 5 min) while arterial blood pressure and heart rate were continuously monitored. Furthermore, the effect of morphine (5 mg/kg) on cardiac output (CO) response to hemorrhage was studied in rats chronically equipped with a mini thermistor for CO monitoring by a thermodilution technique. In addition, plasma catecholamines (HPLC), plasma renin activity (PRA, RIA), vasopressin (RIA), pH, and blood gases were also determined. Morphine administration 30 min after hemorrhage produced a pressor response and tachycardia which were in marked contrast to its depressor effect in intact rats. Morphine elevated PRA and epinephrine but not vasopressin, while blood pH and gases showed no consistent change as compared to salinetreated hemorrhaged rats. Morphine given after the bleeding resulted in enhanced cardiac depression in response to a second bleed of 2 m1l300 g. Our data suggest that activation of pressor mechanisms by morphine during hypovolemic hypotension might enhance vasoconstriction in essential organs, depress cardiac function, and further reduce effective tissue perfusion.}, subject = {Medizin}, language = {en} } @article{SirenFeuerstein1990, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Cardiovascular effects of anatoxin-a in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63103}, year = {1990}, abstract = {Cardiovascular Effects of Anatoxin-A in the Conscious Rat. SJREN, A.-L., AND FEUERSTEIN, G. (1990). Toxicol. Appl. Pharmacol. 102,91-100. The effects ofanatoxin-A on mean arterial pressure (MAP), heart rate, cardiac index (CI), and blood flow (BF) in hindquarter (HQ), renal (R). and mesenteric (M) vascular beds were studied after intravenous (iv) and intracerebroventricular (icv) administration in the conscious rat. The pharmacological profile of anatoxin-A was further compared to nicotine administered iv and icv. MAP and heart rate were measured from femoral artery, CI by thermodilution method, and blood flow by Doppler velocimetry. Anatoxin-A and nicotine (30, 100 and 300 1-!g/kg iv) produced an increase in MAP with concomitant bradycardia. The highest doses increased Cl. MBF and RBF decreased due to a vasoconstriction in M and R vasculature. These effects were attenuated by the ganglion blocker chlorisondamine (5 mg/kg, iv). Anatoxin-A ( 100 1-!g/k~ iv) increased plasma epinephrine Ievels by 2- fold with virtually no effect on norepinephrine whereas nicotine ( 100 ~oLg/kg, iv) increased plasma epinephrine and norepinephrine by 20- to 30-fold. Central administration of anatoxin-A and nicotine (30-100 ,ug/kg icv) increased MAP with no effect on heart rate and produced M and R vasoconstriction. In summary, the present study demonstrates that anatoxin-A acts as a nicotinic cholinergic agonist in the c.onscious rat after both systemic and centrat administration. Anatoxin-A and nicotine produced pressor and reno-splanchnic vasoconstrictor responses and at high doses increased cardiac output. These effects were mediated by activation ofthe nicotinic receptors in the adrenal medulla and sympathetic ganglia. However, marked differences were found in the potency ofanatoxin-A versus nicotine to stimulate the sympathoadrenomedullary axis.}, subject = {Neurobiologie}, language = {en} } @article{PaakkariPaakkariSirenetal.1990, author = {Paakkari, P. and Paakkari, I. and Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Respiratory and locomotor stimulation by low doses of dermorphin - a Mu\(_1\)-receptor mediated effect}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63110}, year = {1990}, abstract = {The selective opioid mu receptor agonist dermorphin increased the locomotor activity of rats dose dependently at 1 0 to 1 00 pmol/kg i.c.v. Respiratory rate, relative tidal volume and respiratory minute volume also increased unrelated to changes in locomotor activity. Higher doses, on the other hand, produced catalepsy and respiratory depression. Pretreatment of the rats with the mu,-selective antagonist naloxonazine (10 mg/kg i.v.) blocked the stimulant locomotor and respiratory effects of low doses of dermorphin (1 0--1 00 pmol/kg), but potentiated the respiratory depressant effect of a high dose (1 0 nmol/kg) of dermorphin. The selective benzodiazepine antagonist flumazenil (5 mg/kg), which has been shown previously to antagonize catalepsy and respiratory depression produced by relatively high doses of dermorphin, did not antagonize the respiratory or locomotor stimulant effect of dermorphin. The data suggest that mu\(_1\)-opioid receptors are responsible for the low dose stimulant effects of dermorphin on locomotor activity and respiration whereas mu\(_2\) receptors mediate the respiratory depressant effect of dermorphin.}, subject = {Neurobiologie}, language = {en} } @article{VonhofSirenFeuerstein1990, author = {Vonhof, S. and Sir{\´e}n, Anna-Leena and Feuerstein, Giora}, title = {Volume-dependent spatial distribution of microinjected thyrotropin-releasing hormone (TRH) into the medial preoptic nucleus of the rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47421}, year = {1990}, abstract = {The present study was performed to qua ntify the distribution of a peptide neurotransmitter after microinjection into the medial preoptic area (POM), using a technique suitable for conscious animal preparations. The results indicate that only 50-ni volumes of injected tracer were sufficiently localized with 77 ± 9\% recovery in the POM. Injections of higher volumes resulted in an increasing spread of tracer into distant anatomical regions and structures, including the needle tract and cerebral ventricles. The amount of tracer localized in the POM decreased to 38±4\% (200 nl) (P < 0.05) and 41 ±8\% (500 nl) (P <0.05), respectively. The data suggest that the volume of injection is critical for intraparenchymal injections into structures of a diameter of I mm or less, such as the POM and should not exceed 50 nl in conscious animal preparations.}, subject = {Neurophysiologie}, language = {en} } @article{ShuaibXuCrainetal.1990, author = {Shuaib, A. and Xu, K. and Crain, B. and Sir{\´e}n, Anna-Leena and Feuerstein, Giora and Hallenbeck, J. and Davis, JN}, title = {Assessment of damage from implantation of microdialysis probes in the rat hippocampus with silver degeneration staining}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47433}, year = {1990}, abstract = {We used a sensitive silver degeneration staining method to study the effects of insertion of microdialysis probes in rat dorsal hippocampus and neocortex. Nine animals were sacrificed 24 h, 3 days or 7 days after implantation of dialysis tubing. Although mild neuronal cell death and small petechial hemorrhages were seen in elose proximity to the implantation site, the striking finding was the presence of degenerating axons both adjacent to the implantation site and in remote sites such as the corpus callosum and contralateral hippocampus. The observed changes could alter brain function near or remote from the implantation site and should be considered in analysis of dialysis experiments.}, subject = {Neurophysiologie}, language = {en} } @article{FeuersteinZerbeSiren1991, author = {Feuerstein, G. and Zerbe, R. L. and Sir{\´e}n, Anna-Leena}, title = {Supraoptic nuclei in vasopressin and hemodynamic responses to hemorrhage in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63057}, year = {1991}, abstract = {CARDIOVASCULAR and vasopressin (A VP) responses to hcmorrhagc wcrc studicd in rats with lesions of the hypothalamic supraoptic nuclei (SONL). Bleeding caused hypotension and increase in heart rate (HR) and A VP. SONL rats failed to fully recover from bleeding as compared to normal rats. Plasma A VP in SONL rats was in the normal in basal conditions, but failed to increase to levels attained in normal rats throughout the post-hemorrhage period. These data suggcst that the supraoptic nuclei are the primary regulatory sitcs for A VP release in rcsponse to hemorrhage and that lack of adequate A VP release significantly retards blood pressure recovery after bleeding.}, subject = {Neurobiologie}, language = {en} } @article{SirenFeuerstein1991, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Hypothalamic opioid µ-receptors regulate discrete hemodynamic functions in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63069}, year = {1991}, abstract = {The effect of the selective \(\mu\)-opioid agonist o-Ala\(^2\)-Me-Phe\(^4\)-Gly-ol'-enkephalin (DAGO), injected into the medial preoptic nucleus of hypothalamus, on cardiac output and regional blood flow was studied in the conscious rat and the effect of DAGO on renal sympathetic nerve activity and renal blood flow was studied in anesthetized rats. In conscious rats, injections of DAGO (1 or 10 nmol) into the preoptic nucleus increased the blood pressure in a dose-related manner. The maximum rises of mean arterial pressure and pulse pressure after the larger dose were +23 ± 5 mmHg (mean ±SEM, P < 0.01) and + 17 ± 3 mmHg(P < 0.01), respectively. A small dose (0.1 nmol) increased heart rate ( +47 ± 13 bpm, P < 0.05); thc 1 nmol dosc produced bradycardia (- 39 ± 11 bpm, P < 0.05), while the 10 nmol dose initially decreased heart rate ( -68 ± 15 bpm (P < 0.01) and then gradually increased heart rate to a maximum of + 74 ± 13 bpm, (P < 0.0 1). A long-lasting increase in cardiac output was also elicited by DAGO, with maximum changes after 1 and 10 nmol of + 14 ± 6\% and +22 ± 7\% (P < 0.01), respectively. B1ood flow in the hindquarters increascd after DAGO but the mesenteric and renal blood ftow decreased in a dose-related manner. Significant responscs in hindquarter and mesenteric blood fl.ow after DAGO were independent of systemic hemodynamic responses at the dose ofO.l nmol. The vascular resistance in the hindquarters significantly decreased after a small dose of DAGO while the larger doses dose-dependently increased mesenteric and renal vascular resistance. A crucial role of the sympathetic nervous system in the hemodynamic effects of DAGO was demonstrated: (1) by the profound activation of renal sympathetic nerve activity after injections of DAGO (I nmol/100 nl) into the preoptic nucleus, (2) by blockade of the pressor, tachycardic and regional hemodynamic effects of DAGO (I nmol) by the ganglion blocker ch1orisondamine (5 mg/kg i.v.). The results suggest that the pressor effect of DAGO in preoptic nucleus is due primarily to an increase in cardiac output. The differential changes in blood ftow in organs further suggest that the opioid \(\mu\)-receptors in the preoptic nucleus might be involved in the integration of peripheral blood ftow in the hypothalamus during affective behavior.}, subject = {Neurobiologie}, language = {en} } @article{VonhofSirenFeuerstein1991, author = {Vonhof, S. and Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Central ventilatory effects of thyrotropin-releasing hormone in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63075}, year = {1991}, abstract = {Thyrotropin-releasing hormonewas shown to exert potent ventilatory effects after centrat administration. These data, however, were derived from studies using anesthetized animal preparations. Since TRH elicits strong arousal reactions, the observed ventilatory effects of TRH under anesthesia may have been due to nonspecific reduction in the anesthetic state of the animals. In order to clarify the extent to which the reversal of anesthesia may change ventilatory parameters after TRH application, we investigated the effect of TRH on Ventilation rate, relative tidal volume, relative respiratory minute volume, CO\(_2\) production CO\(_2\) consumption, and locomotor activity in the conscious, unrestrained rat. Intracerebroventricular application of TRH induced a dose-dependent, sustained increase in ventilation rate, relative tidal volume, and relative respiratory minute volume of maximally 128\%, 890\%, and 235\%, respectively. In addition, CO\(_2\) production and O\(_2\) consumption were elevated by 4.6 and 11.7 fold, whiJe no significant changes in locomotor activity were observed. The results suggest that TRH stimulates ventilation by a mechanism independent of its analeptic properties.}, subject = {Neurobiologie}, language = {en} } @article{AdeyemoShapiraTombaccinietal.1991, author = {Adeyemo, O. M. and Shapira, S. and Tombaccini, D. and Pollard, H. and Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {A goldfish model for evaluation of the neurotoxicit of \(\omega\)-conotoxin GVIA and screening of monoclonal antibodies}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63087}, year = {1991}, abstract = {A Goldfish Model for Evaluation of the Neurotaxicity of \(\omega\)-Conotoxin GVI A and Screening of Monoclonal Antibodies. ADEYEMO, 0. M .. SHAPIRA, S., TOMBACCINI, D., POLLARD, H. 8 .• FEUERSTEIN, G .. AND SIREN, A-L. ( 1991 ). Toxicol. App/. Pharmaco/. 108, 489-496. The neurotoxicity of \(\omega\)-conotoxin (\(\omega\)-CgTx), a potent neuronal voltage-sensitive calcium channel blocker, was measured using a new bioassay. \(\omega\)-CgTx was administered intraperitoneally (ip) to goldfish weighing approximately 1.6 g, and dose-related changes were observed over a 2-hr period. \(\omega\)CgTx induced time- and dose-dependent abnormal swimming behavior (ASB) and mortality. The antitoxin activity of the antiborlies was investigated in vivo by either ( l) preincubation of the antibody with w-CgTx at 4°C overnight, or (2) pretreatment with antibody, 30 min before \(\omega\)CgTx injection in a 10:1 antibody/\(\omega\)-CgTx molar ratio. The LD50 dose of \(\omega\)-CgTx in goldfish was 5 nmol/kg ip, and preincubation of monoclonal antibody (50 nmol/kg ip) with \(\omega\)-CgTx (5 nmol/kg ip) significantly (p < 0.05) reduced mortality. ASB, and toxicity time. The antitoxin activity of the monoclonal antiborlies evidenced in the goldfish bioassay was further tested in the conscious rat. In the rat, the increases in mean arterial pressure and heart rate induced by \(\omega\)-CgTx (0.03 nmol/rat icv) were significantly (p < 0.02 and p < 0.0 l, respectively) attenuated by preincubation of the toxin with the antibody (0.3 nmol/rat). We conclude that the goldfish bioassay provides a simple. accurate, and inexpensive in vivo model for the study of the toxicity of \(\omega\)CgTx}, subject = {Neurobiologie}, language = {en} } @article{SirenVonhofFeuerstein1991, author = {Sir{\´e}n, Anna-Leena and Vonhof, S. and Feuerstein, G.}, title = {Hemodynamic defense response to thyrotropin-releasing hormone injected into medial preoptic nucleus in rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63099}, year = {1991}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{VonhofSiren1991, author = {Vonhof, S. and Sir{\´e}n, Anna-Leena}, title = {Reversal of µ-opioid-mediated respiratory depression by α2-adrenoceptor antagonism}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47454}, year = {1991}, abstract = {The present study was performed in order to evaluate the effects of the selective 02- adrenoceptor antagonist 6-chloro-2,3,4,5-tetrahydro-3-methyl-1H-3-benzazepine (SK\&F 86466) on dermorphin-induced analgesia, respiratory depression and inhibition of locomotor activity in the conscious rat. Intracerebroventricular (icv) administration of dermorphin (3 nmol/rat) decreased respiration rate and relative ventilatory minute volume maximally by 38 \% and 50 \% of baseline respectively. SK\&F 86466 dose-dependently reversed the dermorphin-induced depression of ventilatory parameters, while SK\&F 86466 exerted no effect on dermorphin-induced analgesia or depression of locomotor activity due to catalepsia. It appears, therefore, that a 2-adrenoceptors selectively interact with Jl2-opioid-receptor mediated effects, such as respiratory depression, but are not involved in the modulation of Jl,-opioid-related effects, such as supraspinal analgesia and depression of locomotor activity.}, subject = {Biowissenschaften}, language = {en} } @article{PaakkariPaakkariFeuersteinetal.1992, author = {Paakkari, P. and Paakkari, I. and Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {Evidence for differential opioid µ\(_1\)- and µ\(_2\)-receptor regulation of heart rate in the conscious rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63017}, year = {1992}, abstract = {The possibility that \(\mu\)Opioid-induced tachycardia and bradycardia could be mediated by different subtypes of the \(\mu\)·receptor was studied in conscious Sprague-Dawley rats. The selective \(\mu\)·receptor agonist dermorphin and its analog, TAPS (Tyr-o-Arg-Phe-sarcosine), a putative \(\mu _1\)-receptor agonist, were given centrally. Tyr-o-Arg-Phe-sarcosine increased the heart rate, the response being inversely correlated to the dose (an increase of 71 ± 22, 49 ± 14 and 30 ± 17 beats/min at doses of 0.3, 3 and 30 pmol, respectively). Dermorphin induced less clear changes in heart rate (maximum increase of 39 ± 14 beats/min at the dose of 1 pmol). Aftertreatment with the Jl 1-selective antagonist naloxonazine (NAZ), TAPS 30 pmol and dennorphin I pmol decreased heart rate by -22 ± 10 and -24 ± 7 bpm, respectively. The bradycardic effect oflarger doses of dennorphin was potentiated by NAZ (from -25 ± 8 to -97 ± 22 bpm) but abolished by the non-selective antagonist naloxone. These data suggest that the high affinity \(\mu _1\)-opioid receptors mediate tachycardic responses and \(\mu _2\)-receptors mediate bradycardic responses.}, subject = {Neurobiologie}, language = {en} } @article{AdeyemoSiren1992, author = {Adeyemo, M. and Sir{\´e}n, Anna-Leena}, title = {Cardio-respiratory changes and mortality in the conscious rat induced by (+)- and (±)- anatoxin-a}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63027}, year = {1992}, abstract = {0. M. ADEYEMO and A.-L. SIREN. Cardio-respiratory changes and mortality in the conscious rat induced by ( + )- and ( ± )-anatoxin-a. Toxicon 30, 899-905, 1992.-Anatoxin-a (AnTx-a) isapotent nicotinic cholinergic receptor agonist. The relative potencies of the ( + )-AnTx-a and the racemic mixture ( ± )-AnTxa were investigated in the conscious rat by comparing their effects on mean arterial blood pressure (BP), heart rate (HR), blood oxygen and carbon dioxide pressures (p02 and pC02, respective1y), acid-base balance (pH) and mortality. The present experiments show that while both forms of AnTx-a produce dose-dependent increases in BP and decreases in HR, ( + )-AnTx-a is about IO-fo1d morepotent than the optically inactive isomer. ( + )-AnTx-a was also 6-fo1d more potent than ( ± )-AnTx-a in produclog severe hypoxemia, and more than 4-fold as potent as the (±}-AnTx-a in producing significant hypercapnia accompanied with severe acidosis. The approximate median Iethai dose (Ln so) of ( + )-AnTx-a was about 5-fold less than that of ( ± )-AnTx-a. We conclude that ( + )-AnTx-a is more potent than the ( ± )-AnTx-a racemic mixture in causing detrimental cardio-respiratory changes and therefore increased mortality in the rat.}, subject = {Neurobiologie}, language = {en} } @article{SirenFeuerstein1992, author = {Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {The Opioid System in circulatory control}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63045}, year = {1992}, abstract = {Opioid peptidesandmultiple opioid receptors are found in brain cardiovascular nuclei, autonomic ganglia, the heart, and blood vessels, and opioids induce potent cardiovascular changes. The role of endogenaus opioids in normal cardiovascular homeostasis is unclear; however, current data suggest opioid involvement in stress.}, subject = {Neurobiologie}, language = {en} } @article{DoronMcCarronHeldmanetal.1992, author = {Doron, D. A. and McCarron, D. M. and Heldman, E. and Sir{\´e}n, Anna-Leena and Spatz, M. and Feuerstein, G. and Pollard, H. B. and Hallenbeck, J. M.}, title = {Comparison of stimulated tissue factor expression by brain microvascular endothelial cells from normotensive (WKY) and hypertensive (SHR) rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63032}, year = {1992}, abstract = {The amounts of tissue factor (TF) expressed by brain microvascular endothelial cells (BMECs) from normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) were compared after stimulating the cells with different doses of lipopolysaccharide (LPS), thrombin, phorbol myristic acid (PMA), Ca\(^{2+}\)·ionophore (A23187), or tumor necrosis factor (TNF) and interleukin·l (IL.l). Treatment ofcultured BMECs fron. WKY and SHR with all of these factors dose·dependently increased their total amount of TF; no substantive differences in the Ieveis of enhanced TF expression were observed between WKY and SHR BMECs. We conclude that stimulated endothelium from rats with hypertension, a major stroke risk factor, is not hyperresponsive with respect to TF expression when compared to normotensive controls.}, subject = {Neurobiologie}, language = {en} } @article{SirenHeldmanDoronetal.1992, author = {Sir{\´e}n, Anna-Leena and Heldman, Eliahu and Doron, David and Yue, Tian-Li and Liu, Yong and Feuerstein, G. and Hallenbeck, JM}, title = {Release of proinflammatory and prothrombbtic mediators in the brain and peripheral circulation in spontaneously hypertensive and normotensive Wistar-Kyoto rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47469}, year = {1992}, abstract = {Background and Purpose: We reported previously that stroke risk factors prepared the brain stem for the development of ischemia and hemorrhage and induced the production of tumor necrosis factor following an intrathecal injection of Iipopolysaccharide, a prototypic monocyte-activating stimulus. This study evaluates whether blood or brain cells of hypertensive rats produce more proinflammatory and prothrombotic mediators than do blood or brain cells of normotensive rats. MethotJs: Levels of tumor necrosis factor, platelet-activating factor, 6-ketoprostaglandin F1a, and thromboxane B2 in the cerebrospinal fluid and blood of spontaneously hypertensive and normotensive Wistar-Kyoto rats were monitored before and after achallenge with Iipopolysaccharide. Results: Little or no activity from these media tors was found in the cerebrospinal fluid or blood of saline-injected control animals. Intravenous administration of Iipopolysaccharide (0.001, 0.1, and 1.8 mg/kg) produced dose-dependent increases in blood levels of all mediators in hypertensive rats. In normotensive rats the levels were less than in hypertensive rats and were not c1early dose-related. When Iipopolysaccharide was injected intracerebroventricularly, more tumor necrosis factor was measured in the cerebrospinal fluid than in the blood, suggesting local synthesis of this cytokine. Levels of tumor necrosis factor and platelet-activating factor in the cerebrospinal fluid were higher in hypertensive than in normotensive rats. The thromboxane A2/prostacyclin ratio was not aItered significantly between the two rat strains. Conclusions: It is suggested that the higher incidence of brain stem ischemia and hemorrhage after the intrathecal injection oflipopolysaccharide in hypertensive rats than in normotensive rats might be related to the higher levels of the two cytotoxic factors tumor necrosis factor and platelet-activating factor produced in response to such challenge.}, subject = {Gehirn}, language = {en} } @article{LankiewiczBowersReynoldsetal.1992, author = {Lankiewicz, Leszek and Bowers, Cyril Y. and Reynolds, G. A. and Labroo, Virender and Cohen, Louis A. and Vonhof, Stefan and Sir{\´e}n, Anna-Leena and Spatola, Arno F.}, title = {Biological Activities of Thionated Thyrotropin-Releasing Hormone Analogs}, series = {Biochemical and Biophysical Research Communications}, volume = {184}, journal = {Biochemical and Biophysical Research Communications}, number = {1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128152}, pages = {359-366}, year = {1992}, abstract = {No abstract available.}, language = {en} } @article{SirenMcCarronLiuetal.1993, author = {Sir{\´e}n, Anna-Leena and McCarron, R. M. and Liu, Y. and Barone, F. and Spatz, M. and Feuerstein, G. and Hallenbeck, J. M.}, title = {Perivascular monocyte/macrophage interaction with endothelium as a mechanism through which stroke-risk factors operate to increase stroke likelihood. Research Initiatives in Vascular Disease; SPECIAL COMMUNICATION}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63006}, year = {1993}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{PaakkariPaakkariLandesetal.1993, author = {Paakkari, P. and Paakkari, I. and Landes, P. and Sir{\´e}n, Anna-Leena and Feuerstein, G.}, title = {Respiratory \(\mu\)-Opioid and benzodiazepine interactions in the understrained rat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62974}, year = {1993}, abstract = {lnteractions of p-opioid receptors with the benzodiazepine system were studied by examining the modulatory effects of flumazenil (a benzodiazepine antagonist) and alprazolam (a benzodiazepine agonist) on the respiratory effects ofthe opioid peptide dermorphin. Dermorphin, 1-30 nmol administered i.c.v., to conscious, unrestrained rats decreased ventilation rate (VR) and minute volume (MV) dose-dependently. The ventilatory depression was antagonized by naloxone and by the benzodiazepine antagonist flumazenil. The benzodiazepine alprazolam potentiateri the respiratory inhibition of a small (I nmol) dose of dermorphin but antagonized that of a higher dos:~ (3 nmol). The results suggest that the benzodiazepine/GABA receptor complex modulates respiratory depression induced by centrat p-receptor Stimulation in the rat.}, subject = {Neurobiologie}, language = {en} } @article{PaakkariPaakkariVonhofetal.1993, author = {Paakkari, P. and Paakkari, I. and Vonhof, S. and Feuerstein, G. and Sir{\´e}n, Anna-Leena}, title = {Dermorphin analog Tyr-D-Arg\(^2\)-Phe-sarcosine-induces opioid analgesia and respiratory stimulation - the role of Mu\(_1\)- receptors?}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62984}, year = {1993}, abstract = {Tyr-o-Arg\(^2\)-Phe-sarcosine\(^4\) (TAPS), a mu-selective tetrapeptide analog of dermorphin, induced sustained antinociception and stimulated ventilatory minute volume (MV) at the doses of 3 to 100 pmol i.c.v. The doses of 30 and 100 pmol i.c.v. induced catalepsy. The effect of TAPS on MV was in negative correlation with the dose and the maximal response was achieved by the lowest (3 pmol) dose (+63 ± 23\%, P < .05). Morphine, an agonist at both mu\(_1\) and mu\(_2\) sites, at a dose of 150 nmol i.c.v. (equianalgetic to 100 pmol of TAPS decreased the MV by 30\%, due to a decrease in ventilatory tidal volume. The antinociceptive effect of TAPS was antagonized by naloxone and the mu, receptor antagonist, naloxonazine. Naloxonazine also attenuated the catalepsy produced by 1 00 pmol of TAPS i.c. v. and the respiratory Stimulation produced by 3 pmol of TAPS i.c.v. Pretreatment with 30 pmol of TAPS antagonized the respiratory depression induced by the mu opioid agonist dermorphin (changes in MV after dermorphin alone at 1 or 3 nmol were -22 ± 1 0\% and -60 ± 9\% and, after pretreatment with TAPS, +44 ± 11 \% and -18 ± 5\%, respectively). After combined pretreatment with naloxonazine and TAPS, 1 nmol of dermorphin had no significant effect on ventilation. In contrast, pretreatment with a low respiratory stimulant dose (10 pmol i.c.v.) of dermorphin did not modify the effect of 1 nmol of dermorphin. ln conclusion, the antinociceptive, cataleptic and respiratory stimulant effects of TAPS appear to be a related to its agonist action at the mu, opioid receptors. TAPS did not induce respiratory depression (a mu\(_2\) opioid effect) but antagonized the respiratory depressant effect of another mu agonist. Thus, in vivo TAPS appears to act as a mu\(_2\) receptor antagonist.}, subject = {Neurobiologie}, language = {en} } @article{XuNaeveriFrerichsetal.1993, author = {Xu, K. and N{\"a}veri, L. and Frerichs, K. and Hallenbeck, J. M. and Feuerstein, G. and Davis, J. N. and Sir{\´e}n, Anna-Leena}, title = {Extracellular catecholamine levels in rat hippocampus after a selective alpha2-adrenoceptor antagonist or a selective dopamnie uptake inhibitor: Evidence for dopamine release from local dopaminergic nerve terminals}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62997}, year = {1993}, abstract = {The effect of 6-chloro-2,3,4,5-tetrahydro-3-methyi-1-H-3-benzazepine (SKF 86466), a selectlve nonimldazoline alpha-2 adrenoceptor antagonlst, on hippocampal re1ease of norepinephrine and dopamlne in conscious rats was lnvestigated by /n vlvo mlcrodialysis and high-pressure liquid chromatography. Additionally, extracellular concentrations of hippocampal dopamine (DA) and norepinephrtne (NE), durtng Infusion of selective monoamine uptake Inhibitors, were determined in freely moving rats. The basal concentration of NE in the dialysate was 4.9 ± 0.3 pg/20 pl. lntravenous admlnistratlon of 5 or 10 mgJkg of SKF 86466 was associated wlth a transierlt inc:rease (30 min) of 2-fold (12 ± 1 pg/20 ,d; p < .05) and 8-fold (39 ± 3 pg/20 pl; p < .05), respectlvely, in dlalysate NE, whereas a 1-mgfkg dose had no effect. DA was not detected in basal dlalysates, but after the adminlstratlon of 5 or 10 mgJkg of SKF 86466, 3.9 ± 0.4 and 6.4 ± 0.6 pg/20 pl, respectlvely, was present in the dialysates. The rnaxlmum increase in dialysate DA was reached 60 to 90 min after SKF 86466. The DA was not derived from plasma because plasma NE was elevated after the 5 mgJkg dose of SKF 86466 whereas no plasma DA was detected. ln order to determlne whether DA was present in noradrenergic nerve termlnals, the dopamine ß-hydroxylase Inhibitor SKF 1 02698 was administered (50 mgJkg i.p.). The Inhibitor decreased dialysate NE but DA was stin not detected in the dialysate. When SKF 86466 (5 mgJkg t.v.) was adminlstered 4 hr after SKF 102698, DA appeared in the dialysate but there was no lncrease in dialysate NE. Administration through the dialysis probe of the DA uptake Inhibitor, GBR-12909 (0.1 and 1 pM), dose-dependently lnaeased DA Ieveis to 5.7 ± 1.2 and 9.6 ± 2.8 pg/20 pl, respectively. GBR-12909 had no effect on hippocampal NE. Desipramine (5 and 10 pM) lncreased dose-dependently dialysate NE and lncreased DA concentrations to detectable Ieveis (2.7 ± 0.5 and 3.5 ± 0.7 pg/20 ,d, respectively). These results suggest that the a/pha-2 adrenoceptors modulate both NE and DA release in the rat hlppocampus and that DA detected in the hlppocampal dialysate might be released from dopaminergic neurons.}, subject = {Neurobiologie}, language = {en} } @article{SirenLiuFeuersteinetal.1993, author = {Sir{\`e}n, Anna-Leena and Liu, Y. and Feuerstein, G. and Hallenbeck, JM}, title = {Increased release of tumor necrosis factor alpha into the cerebrospinal fluid and peripheral circulation of aged rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47997}, year = {1993}, abstract = {Background and Purpose: We earlier reported that risk factors for stroke prepare brain stem tissue for a modified Shwartzman reaction, incIuding the development of ischemia and hemorrhage and the production of tumor necrosis factor-a, after a provocative dose of lipopolysaccharide. In the present study, we sought to determine whether blood and central nervous system cells of rats with the stroke risk factor of advanced age produce more proinflammatory and prothrombotic media tors than do those of young rats of the same strain. Methods: Levels of tumor necrosis factor-a and platelet activating factor in the cerebrospinal fluid and tumor necrosis factor-a in the serum of 2-year-old and 16-week-old Sprague-Dawley rats were monitored before and after challenge with lipopolysaccharide. Results: No consistent tumor necrosis factor-a activity was found in the cerebrospinal fluid or blood of control animals. Intravenous administration of lipopolysaccharide (1.8 mg/kg) increased serum tumor necrosis factor-a levels but had no effect on tumor necrosis factor-a in the cerebrospinal fluid. Serum tumor necrosis factor-a increased much more in aged rats than in young rats. When lipopolysaccharide was injected intracerebroventricularly, tumor necrosis factor-a activity in cerebrospinal fluid increased significantly more in old rats than in young rats. Baseline levels of platelet activating factor in cerebrospinal fluid were significantly higher in old rats than in young rats, and the levels increased to a greater degree in aged rats on stimulation. Conclusions: Rats with the stroke risk factor of advanced age respond to lipopolysaccharide with a more exuberant production of tumor necrosis factor-a and platelet activating factor than young rats of the same strain. These findings are consistent with our working hypothesis that perivascular cells are capable of exaggerated signaling of endothelium through cytokines such as tumor necrosis factor-a in animals with stroke risk factors. The effect of such signaling might be to prepare the endothelium of the local vascular segment for thrombosis or hemorrhage in accord with the local Shwartzman reaction paradigm.}, subject = {Gehirn}, language = {en} } @article{LiuMcDonnellYoungetal.1993, author = {Liu, T. and McDonnell, PC and Young, PR and White, RF and Sir{\`e}n, Anna-Leena and Hallenbeck, JM and Barone, FC and Feuerstein, Giora}, title = {Interleukin-1ß mRNA expression in ischemic rat cortex}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47442}, year = {1993}, abstract = {Background and Pur pose: Interleukin-1ß is a proinftammatory cytokine produced by blood-borne and resident brain inftammatory cells. The present study was conducted to determine if interleukin-1ß mRNA was produced in the brain of rats subjected to permanent focal ischemia. Methods: Rat interleukin-1ß cDNA, synthesized from stimulated rat peritoneal macrophage RNA by reverse transcription and polymerase chain reaction and c10ned in plasmid Bluescript KS+, was used to evaluate the expression of interleukin-1ß mRNA in cerebral cortex from spontaneously hypertensive rats and normotensive rats subjected to permanent middle cerebral artery occlusion. Interleukin-1ß mRNA was quantified by Northern blot analysis and compared with rat macrophage RNA standard. To correct for gel loading, blots were also analyzed with cyclophilin cDNA, which encodes an abundant, conserved protein that was unchanged by the experimental conditions. Results: Interleukin-1ß mRNA produced in the ischemic zone was significantly increased from 6 hours to 120 hours, with a maximum of211±24\% ofinterleukin-1ß reference standard, ie, 0.2 ng stimulated rat macrophage RNA, mRNA compared with the level in nonischemic cortices (4±2\%) at 12 hours after ischemia (P<.OI; n=6). Interleukin-1ß mRNA at 12 hours after ischemia was markedly elevated in hypertensive rats over levels found in two normotensive rat strains. Neurological deficits were also apparent only in the hypertensive rats. Conclusions: Brain interleukin-1ß mRNA is elevated acutely after permanent focal ischemia and especially in hypertensive rats. These data suggest that this potent proinflammatory and procoagulant cytokine might have a role in brain damage following ischemia.}, subject = {Gehirn}, language = {en} } @techreport{McCarronDoronSirenetal.1994, author = {McCarron, R. M. and Doron, D. A. and Sir{\´e}n, Anna-Leena and Feuerstein, G. Z. and Heldman, E. and Pollard, H. B. and Spatz, M. and Hallenbeck, J. M.}, title = {Agonist-stimulated release of von Willebrand factor and procoagulant factor VIII in rats with and without risk factors for stroke [Research Report]}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62945}, year = {1994}, abstract = {Lipopolysaccharidc (LPS)-induced (i.v. or i.c.v., 1.8 mg/kg) release of von Willebrand factor (vWF) ·was examined in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats. SHR rats releascd significantly (P < 0.05) more vWF than WKY rats in response to LPS. LPS also inhibited factor VIII procoagulant activity (FVIII: c) which may indicate an increase in thrombin activity. Cultured cerebrovascular endothelial cells (EC) derived from both SHR and WKY rats, as weil as human umbilical vein EC (HUVEC) cultures constitutively released vWF. Treatment with agonists including LPS, thrombin and tumor necrosis factor-a (TNFa) did not affect the in vitro secretion of vWF by cerebrovascular EC cultures but significantly upregulated vWF release by HUVEC cultur~s. Preincubation of cerebrovascular EC cultures with interleukin-1 OL-l) ± TNFa or co-culturing in the presence of LPS-activated syngeneic monocytes had no effect on vWF secretion. The findings demoostrate that conditions of hypertension may affect endothelial cells and make them more responsive to agonist Stimulation and thereby increase secretion of vWF, an important factqr in hemostasis as weil as thrombosis. The capacity of LPS to significantly affect the in vivo secretion of vWF in SHR and WKY rats but not cultured cerebrovascular EC indicates that observed elevations in plasma vWF were not derived from cerebrovascular EC. lt is suggested that hypertension may function as a risk factor for thrombotic stroke by influencing factors involved in coagulation processes, such as vWF and factor VIII : c.}, subject = {Neurobiologie}, language = {en} } @techreport{WangSirenLiuetal.1994, author = {Wang, X. and Sir{\´e}n, Anna-Leena and Liu, Y. and Yue, T-L. and Barone, F. C. and Feuerstein, G. Z.}, title = {Upregulation of intercellular adhesion molecule-1 (ICAM-1) on brain microvascular endothelial cells in rat ischemic cortex [Research Report]}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62952}, year = {1994}, abstract = {The expression of intercellular adhesion molecule 1 (ICAM-1) was studied in rat focal ischemic cortex. A significant increase in ICAM-1 mRNA expression in the ischemic cortex over Ievels in contralateral (nonischemic) site was observed by means of Northern blot analysis following either permanent or temporary occlusion with reperfusion of the middle cerebral artery (PMCAO or MCAO with reperfusion) in spontaneously hypertensive rats. In the ischemic cortex, Ievels of ICAM-1 mRNA increased significantly at 3 h (2.6-fold, n = 3, P < 0.05), peaked at 6 to 12 h (6.0-fold, P < 0.01) and remained elevated up to 5 days (2.5-fold, P < 0.05) after PMCAO. The profile of ICAM-1 mRNA expression in the ischemic cortex following MCAO with reperfusion was similar to that following PMCAO, except that ICAM-1 mRNA was significantly increased as early as 1 h (6.3-fold, n = 3, P < 0.05) and then gradually reached a peak at 12 h (12-fold, P < 0.01) after reperfusion. ICAM-1 mRNA expression in ischemic cortex following PMCAO was significantly greater in hypertensive rats than in two normotensive rat strains. Immunostaining using anti-ICAM-1 antiborlies indicated that upregulated ICAM-1 expressionwas localized to endotheIial cells of intraparenchymal blood vessels in the ischemic but not contralateral cortex. The data suggest that an upregulation of ICAM-1 mRNA and protein on brain capillary endothelium may play an important rote in leukocyte migration into ischemic brain tissue.}, subject = {Neurobiologie}, language = {en} } @article{McCarronWangSirenetal.1994, author = {McCarron, R. M. and Wang, L. and Sir{\´e}n, Anna-Leena and Spatz, M. and Hallenbeck, J. M.}, title = {Monocyte adhesion to cerebromicrovascular endothelial cells derived from hypertensive and normotensive rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-62960}, year = {1994}, abstract = {No abstract available}, subject = {Neurobiologie}, language = {en} } @article{YongJacobowitzBaroneetal.1994, author = {Yong, Liu and Jacobowitz, David M. and Barone, Frank and McCarron, Richard and Spatz, Maria and Feuerstein, Giora and Hallenbeck, John M. and Sir{\´e}n, Anna-Leena}, title = {Quantitation of perivascular monocyte / macrophages around cerebral blood vessels of hypertensive and aged rats}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86800}, year = {1994}, abstract = {The numbers of monocytes and macrophages in the walls of cerebral blood vessels were counted on perfusion-fixed frozen brain sections (16 JLffi) of spontaneously hypertensive rats (SHR), stroke-prone SHR (SHR-SP), normotensive Wistar-Kyoto (WKY) rats, and young (16-week-old) and old (2-year-old) normotensive Sprague-Dawley rats (SD-l6w and SD-2y, respectively) using monoclonal antiborlies against rat macrophages (ED2). The staining was visualized with fluoresceinlabeled second antiborlies. The ED2-specific staining in brain sections was restricted to macrophages in a perivascular location. The number of perivascular cells per square millimeter of high-power field was significantly greater in SHR-SP (8.6 ± 2.1; n = 4) and SHR (6. 7 ± 0.9; n = 6) than in normotensive WKY (4.0 ± 0.5; n = 6; p <0.01). The number of perivascular macrophages was also greater in SD-2y (7.5 ± 2.7; n = 9) than in SD-l6w (2.9 ± 1.8; n = 8; p < 0.01). No ED2 staining was found in the resident microglia or in the endothelial cells, which were identified by double staining with rhodamine-labeled anti-factor VIII-related antigen antiborlies. The results suggest that the stroke risk factors hypertension and advanced age are associated with increased subendothelial accumulation of monocytes and macrophages. This accumulation could increase the tendency for the endothelium to convert from an anticoagulant to a procoagulant surface in response to mediators released from these subendothelial cells.}, subject = {Willebrand-Faktor}, language = {en} } @article{McCarronWangSirenetal.1994, author = {McCarron, R. M. and Wang, L. and Sir{\´e}n, Anna-Leena and Spatz, M. and Hallenbeck, J. M.}, title = {Adhesion molecules on normotensive and hypertensive rat brain endothelial cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86819}, year = {1994}, abstract = {The intercellular adhesion of circulating leukocytes to vascular endothellum ls a prerequisite for leukocyte emigration from the blood to extravascular tlssues. This process is facllltated by adhesion molecules on the surfaces of both the vascular endothelial cells and the leukocytes. The experiments presented here demonstrate for the first time that the leukocyte adhesion receptor, intercellular adhesion molecule-1, is constitutively expressed on cultured cerebromicrovascular endothelial cell lines derived from both spontaneously hypertensive (SHR) rats and normotensive WistarKyoto (WKY) rats. Both cultures contained simliar numbers of cells constitutively expressing this adhesion molecule (31.4\% and 29.6\%, respectlvely). Adhesion molecule expression was up-regulated by interleukin-1 ß, tumor necrosis factor-a, interferon-y and lipopolysaccharide in a dose- and time-dependent manner. Both cultures exhibited similar maximum levels of adhesion molecule up-regulation to optimal concentrations of all three cytokines. However, SHR endothelial cells were moresensitive to all three cytokines; significantly higher levels of intercellular adhesion molecule-1 expresslon were seen on SHR as opposed to WKY endothelial cells cultured with sub-optimal cytokine concentrations. It was also observed that lipopolysaccharide up-regulated intercellular adhesion molecule-1 expression on SHR endothelial cells to a greater extent than on WKY endothelial cells. The findings that intercellular adhesion molecule-1 can be up-regulated to a greater degree on SHR endothelial cells may have important implications for in vivo perivascular leukocyte accumulation under hypertensive conditions. These observations indicate a possible mechanism by which hypertension may predispose to the development of disorders such as atherosclerosis and stroke.}, subject = {Endothelzelle}, language = {en} } @phdthesis{Schichor2000, author = {Schichor, Christian}, title = {Entwicklung eines organotypischen In-vitro-Assays zur Analyse der Gliominvasion}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-4668}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2000}, abstract = {Die Gliominvasion in weißer Substanz des Gehirns stellt eines der unbew{\"a}ltigten klinischen Probleme dar. In dieser Arbeit wird die Entwicklung eines in vitro Assays beschrieben, der es erm{\"o}glicht, die Gliominvasion an einem Hirnschnitt zu verfolgen und zu quantifizieren.}, language = {de} } @phdthesis{Hoehlriegel2002, author = {H{\"o}hlriegel, Nicole}, title = {Der Einfluss von neurotrophen Faktoren auf das biologische Verhalten von Medulloblastomen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-7838}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2002}, abstract = {In der vorliegenden Arbeit wurde das biologische Verhalten von Medulloblastomen unter dem Einfluss neurotropher Faktoren untersucht. Diese verwendeten Neurotrophine wirken innerhalb der untersuchten Medulloblastom-Zellinien und -Prim{\"a}rkulturen in unterschiedlicher Weise auf Proliferation, Migration und das Invasionsverhalten der Tumorzellen. Dies geschieht in Abh{\"a}ngigkeit der exprimierten Neurotrophin-Tyrosinkinase-Rezeptoren auf der Zelloberfl{\"a}che. Der brain-derived neurotrophic factor (BDNF) konnte in den Zellinien MHH-Med 2 und MHH-Med 4 das Wachstumsverhalten hemmen. Desweiteren wurde die Apoptoserate der ZL 4 unter BDNF-Behandlung gesteigert. Die Wirkung dieses neurotrophen Faktors wird {\"u}ber den Rezeptor Trk B vermittelt. Durch den Nachweis der aktivierten Form der MAP-Kinase unter BDNF-Stimulation, sowohl in der ZL MHH-Med 4 und auch in MEB-Med 8S zeigt, dass BDNF in Medulloblastomen ebenfalls {\"u}ber Trk B wirkt. Im Gegensatz zu BDNF, welcher die Zellmotilit{\"a}t nicht beeinflusste, konnte das neurotrophin-3 (NT-3) das Wanderungsverhalten der ZL 4 hemmen. Dieser Effekt ließ sich durch Zugabe des blockierenden Antik{\"o}rpers gegen NT-3 wieder aufheben. Die f{\"u}r die Vermittlung des Effektes notwendige Rezeptortyrosinkinase Trk C konnte auf der Oberfl{\"a}che dieser Zellinie nachgewiesen werden. {\"U}ber den Nachweis der phosphorylierten Form der MAP-Kinase nach NT-3-Stimulation wurde auch hier die Wirkvermittlung {\"u}ber den zugeh{\"o}rigen Rezeptor best{\"a}tigt. Somit konnte gezeigt werden, dass die neurotrophen Faktoren in Abh{\"a}ngigkeit der zugeh{\"o}rigen Rezeptor-Tyrosinkinasen unterschiedlichste physiologische Zellreaktionen bewirken. Durch den inkonstanten Rezeptorbesatz der untersuchten ZL und auch die gegenseitige Beeinflussung der verschiedenen Aktivit{\"a}tszust{\"a}nde der jeweiligen Rezeptoranteile ebenso wie durch die Hinweise auf autokrine Loops durch die Medulloblastomzellen kann eine einfache Faktor-Wirkung-Beziehung nicht aufgestellt werden und bleibt somit Bestandteil weiterer Untersuchungen.}, language = {de} } @phdthesis{Zuechner2003, author = {Z{\"u}chner, Mark}, title = {Auswirkungen einer moderaten Hypothermie auf das neurologische Outcome, das histologische und kernspintomographische Sch{\"a}digungsausmaß nach Induktion einer epiduralen fokalen Raumforderung im Tiermodell}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-9034}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2003}, abstract = {In dieser experimentellen Studie wurde der Einfluss einer moderaten Hypothermie nach Induktion einer epiduralen, extraaxialen Raumforderung auf das neurologische Outcome, auf histopathologische Ver{\"a}nderungen und mittels bildgebender Methoden untersucht. Der Hauptaugenmerk wurde dabei eindeutig auf die neurologischen Verlaufsuntersuchungen mit Hilfe einer neuropsychologischen Testbatterie gelegt.Damit konnte in etwa die Hauptphase der klinischen Rekonvaleszens nach Trauma abgedeckt werden.Zudem hatten die meisten experimentellen Arbeiten bereits nach wesentlich k{\"u}rzeren Zeitr{\"a}umen ihre Nachuntersuchungen abgeschlossen.Die Gesamtmortalit{\"a}t betrug bei den normotherm behandelten Tieren 55\% und bei den hypotherm behandelten Tieren 45\%. Der Unterschied betrug damit nur 10\% und war nicht signifikant. Betrachtet man aber die Mortalit{\"a}tsraten differenzierter, so zeigt sich bez{\"u}glich der rein sch{\"a}digungsbedingten Mortalit{\"a}t als Folge von schweren neurologischen Defiziten wie Hemiparese, Inaktivit{\"a}t und damit verbundenen dramatischen Gewichtsverlust eine Mortalit{\"a}t von 5\% f{\"u}r die Hypothermiegruppe und 30\% in der Normothermiegruppe. Dies findet seine Best{\"a}tigung auch in anderen experimentellen Untersuchungen. F{\"u}r die Anwendung von Hypothermie bei Sch{\"a}del - Hirn -Traumen und zerebralen Isch{\"a}mien in klinischen Studien ist die Datenlage bisher noch widerspr{\"u}chlich. Die bisher gr{\"o}ßte Multicenterstudie in den USA von 1994 -1998 musste bei 392 Patienten mit SHT abgebrochen werden, nachdem kein therapeutischer Effekt unter Hypothermie festzustellen war (Clifton et al., 2001¹). N{\"a}here Analysen zeigten jedoch eine Verbesserung des Outcomes bei Patienten unter 45 Jahren welche bei Aufnahme bereits hypothermen Bedingungen ausgesetzt waren. Damit stellt sich nat{\"u}rlich die Frage nach dem optimalen Zeitfenster f{\"u}r den Beginn einer hypothermen Behandlung. Als therapeutische Konsequenz erscheint damit unter Umst{\"a}nden ein sofortiger Beginn der Hypothermiebehandlung mit Eintreffen des Notarztes als wirkungsvoller. Zus{\"a}tzlich konnten wiederum neueste Untersuchungen bei Patienten mit zerebraler Isch{\"a}mie nach Herz- und Kreislaufstillstand einen protektiven Effekt einer moderater Hypothermie auf das neurologische Outcome aufzeigen (Bernard et al., 2002; Holzer et al., 2002).In unserer Studie sollte aber auf keinen Fall der nur geringe Unterschied in der Gesamtmortalit{\"a}t mit 55 \% in der normothermen und 45 \% in der hypothermen Gruppe vernachl{\"a}ssigt werden. Die Ann{\"a}herung der Gesamtmortalit{\"a}t war hierbei auf eine deutlich erh{\"o}hte Rate systemischer oder lokaler Infektionen unter den hypothermen Tieren zur{\"u}ckzuf{\"u}hren.In klinischen Studien mehren sich allerdings die Hinweise auf eine durch Hypothermie bedingte Immunsuppression und damit verbundenen erh{\"o}hten Infektionsneigung. So konnten erh{\"o}hte Pneumonieraten (Schwab et al., 1998; 2001 ; Shiozaki et al., 2001) aber auch ein vermehrtes Auftreten von Meningitiden (Shiozaki et al.,2001) beobachtet werden. Shiozaki konnte zudem signifikant erh{\"o}hte Raten von Leuko- und Thrombozytopenien sowie Elektrolytentgleisungen im hypothermen Kollektiv finden (Shiozaki et al., 2001). Schwab fand in einer eigens zur {\"U}berpr{\"u}fung der Nebenwirkungen von Hypothermie bei Patienten mit zerebraler Isch{\"a}mie aufgelegten Studie erh{\"o}hte Raten an Pneumonien (48\%), Thrombozytopenien (70\%) und Bradykardien (62\%) (Schwab et al.,2001). Prospektive Studien von Patienten mit kolorektalen Eingriffen wiesen ebenso unter milder Hypothermie signifikant vermehrt Wundheilungsst{\"o}rungen (Kurz et al., 1996) und eine geringere Lymphozytenaktivit{\"a}t auf (Beilin et al., 1998). Angewandt auf unsere Studie zeigte sich ebenfalls eine erh{\"o}hte Rate von Wundheilungsst{\"o}rungen unter Hypothermie, ohne dabeijedoch zu einer Beeinflussung der Ergebnisse in den neuropsychologischen Testreihen zu f{\"u}hren.Abschließend kann festgehalten werden, dass in dieser Studie die Induktion einer moderaten Hypothermie nach epiduraler, extraaxialer Raumforderung, zu einer Verbesserung neurologischer Defizite und damit zu einer Besserung der Lebensqualit{\"a}t jener Versuchstiere f{\"u}hrte, die den Beobachtungszeitraum {\"u}berlebten. Eine Verringerung der Gesamtmortalit{\"a}t konnte nicht erreicht werden.}, language = {de} } @phdthesis{Kiderlen2003, author = {Kiderlen, Michael}, title = {Einfluss des Tyrosinkinaseninhibitors PTK 787/ZK 222584 auf Vaskularisation und Wachstum intracerebraler Gliome der Ratte}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-6272}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2003}, abstract = {Einfluss des VEGFRezeptor-2 spezifischen RTK-Inhibitors PTK 787/ ZK 222584 auf Angiogenese und somit Wachstum maligner Gliome in einem Tiermodell. Verwendet wurden hierbei C6-Rattengliomzellen aus denen durch retrovirale Transfektion von VEGF cDNA in sense Richtung ein stark VEGF exprimierender Zellklon generiert wurde.}, language = {de} } @phdthesis{Franz2004, author = {Franz, Stefanie}, title = {Die Expression von Matrix-Metalloproteasen in humanen Medulloblastomen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-14546}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2004}, abstract = {Im Rahmen dieser Arbeit wurde anhand von Tumorzelllilien und Nativ-Material untersucht, ob und in welchem Masse Medulloblastome verschiedene Matrix-Metalloproteasen exprimieren. Diese Enzyme spielen bei der Gewebeumstrukturierung und Neoangiogenese im Rahmen der Tumorinvasivit{\"a}t eine wesentliche Rolle. {\"U}ber das Verteilungsmuster bei Medulloblastomen ist im Vergleich zu anderen Hirntumoren wie das Glioblastom bisher wenig bekannt. Dies ist ein erster Ansatz, um mittels Vergleich mit dem Vorkommen in Glioblastomen mehr {\"u}ber die MMP-Expression und -verteilung im MDB zu erfahren. Die Analyse erfolgte mittels PCR auf RNA-Ebene und {\"u}ber immunhistochemische F{\"a}rbungen sowie Zymografie auf Proteinebene.}, language = {de} } @phdthesis{Hildebrandt2004, author = {Hildebrandt, Sabine}, title = {Spontane Regression experimenteller Gliome - Vergleich des Spontanverlaufes intracerebraler Gliome bei immunkompetenten und thymektomierten Ratten anhand immunhistologischer und MRT-Studien im Rahmen der C6-Gliomsph{\"a}roidimplantation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-9954}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2004}, abstract = {Gegenstand der vorliegenden Arbeit war die Beschreibung einer in fr{\"u}heren Versuchsserien zuf{\"a}llig gemachten Beobachtung, dass es zu einer Spontanregression experimenteller Gliome kommt. Dies geschah mittels eines Vergleichs des Spontanverlaufs intracerebraler Gliome bei immunkompetenten und thymektomierten Ratten anhand immunologischer und MRT- Studien. Verwendet wurden C6-Rattengliomzellen. Daraus wurden ca. 300 \&\#61549;m große Tumorsph{\"a}roide hergestellt, die beiden Rattenst{\"a}mmen (16 immunkompetenten und 16 immunsupprimierten Sprague- Dawley-Ratten) in den Kortex des linken Frontallappens implantiert wurden. Mittels der MR-Tomographie wurden die Tiere an definierten Terminen auf das Tumorwachstum hin untersucht. Anschließend wurde jeweils eine bestimmte Anzahl an Tumorproben entnommen und mittels der H{\"a}matoxylin- Eosin- bzw. immunhistochemischen F{\"a}rbungen aufgearbeitet. Mittels der Kernspintomographie konnte gezeigt werden, dass die thymektomierten Ratten um 31 \% gr{\"o}ßere Tumoren aufweisen als die immunkompetenten Ratten. Dies wird ebenso bei der histologischen Auswertung der Tumorvolumina (anhand von HE- Schnitten) verdeutlicht. Ebenso konnte aber auch gezeigt werden, dass die Tumorvolumina nach Erreichen des Volumenmaximums (zwischen dem 28.- 30. Tag nach Implantation) in beiden Populationen stark r{\"u}ckl{\"a}ufig sind, um nach dem 72. Tag nach Implantation fast vollst{\"a}ndig zu verschwinden. Im Hinblick auf m{\"o}gliche immunologische Einflussfaktoren, die bislang noch nicht gekl{\"a}rt werden konnten, sind folgende Ergebnisse zu nennen: Zytotoxische T- Zellen sind in immunkompetenten Ratten in etwas h{\"o}herer Anzahl nachzuweisen als in thymektomierten Ratten.}, language = {de} } @phdthesis{Schuler2005, author = {Schuler, Patrick}, title = {Lokalisation und Blockade der Serinprotease uPA im C6-Glioblastom-Modell der Ratte}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-18967}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2005}, abstract = {Gegenstand dieser Doktorarbeit war die Beschreibung des Urokinaseplaminaktivators uPA im C6-Sph{\"a}roidmodell der Ratte und dessen Lokalisation in Bezug auf den Prim{\"a}rtumor. Das hierbei verwendete Tiermodell basiert auf der C6-Tumorzellreihe, welche durch Transfektion von Rattengliomzellen mit dem Vaskularisierungsfaktor VEGF entwickelt wurde. Die gesteigerte Expression von VEGF resultiert in einer st{\"a}rkeren Vaskularisierung und einer erh{\"o}hten Wachstumsrate des Tumors. Im Vorfeld der Tumorimplantation konnte die Expression von uPA durch die C6-Tumorzellen mittels reverser RNA-Transkription und Polymerasekettenreaktion nachgewiesen werden. In vitro gelang der Nachweis von uPA im C6-Sph{\"a}roiden mittels Fluoreszenz-F{\"a}rbung. Im Rahmen des Tierversuches wurden aus den Tumorzellen ca. 300µm große Sph{\"a}roide hergestellt, welche den Ratten in den Kortex des linken Frontallappens implantiert wurden und dort solide Hirntumoren bildeten. Die Versuchstiere wurden anschließend in zwei Gruppen aufgeteilt. Der Positivgruppe wurde t{\"a}glich {\"u}ber einen Zeitraum von 19 bzw. 21 Tagen der Proteasehemmer WX-UK1 in die Bauchh{\"o}hle injiziert, die Kontrollgruppe erhielt ein Placebo. Nach Ablauf des Behandlungszeitraumes konnte an den explantierten Gehirnen mittels histochemischer Peroxidasef{\"a}rbung die Protease uPA im Tumorgewebe nachgewiesen werden. Die Konzentration von uPA war besonders im invasionsaktiven Bereich des Tumors erh{\"o}ht. Dieser entspricht der Randzone des soliden Tumors, sowie den distanzierten Zellnestern im gesunden Hirngewebe, welche als so genannte Invasionszone zusammengefasst werden. Die tragende Rolle von uPA bei der Invasion der Tumorzellen in das gesunde Hirngewebe konnte somit best{\"a}tigt werden. Die Messung von erh{\"o}hten uPA-Konzentrationen an der Basalmembran von Hirngef{\"a}ßen korreliert mit Beobachtungen, dass die Tumorzellen entlang von Gef{\"a}ßen und Plexus migrieren, aber nicht in der Lage sind, in das Gef{\"a}ßlumen einzudringen. Der Nachweis der erfolgreichen orthotopen Sph{\"a}roidimplantation mittels MRT-Bildgebung der Hirntumoren unterstreicht den Vorteil der offenen Implantationstechnik gegen{\"u}ber der Zellinjektion. Die peritoneale Verabreichung des Proteasehemmers WX-UK1 f{\"u}hrte im Rahmen dieser Untersuchungen zu keiner signifikanten Reduktion des Tumorwachstums, welches mittels Volumenmessung im MRT dokumentiert wurde. Des Weiteren konnte keine Minderung der uPA-Konzentration in den Tumoren der Positivgruppe gegen{\"u}ber der Kontrollgruppe gemessen werden. Neben der fehlenden Biodistribution des Wirkstoffes kommt hierf{\"u}r auch eine mangelnde Spezifit{\"a}t von WX-UK1 f{\"u}r uPA oder ein alternativer Aktivierungsweg der Proteolyse innerhalb der Tumorzellen in Betracht. Diese Arbeit f{\"u}hrt zur Weiterentwicklung des C6-Sph{\"a}roidmodells und unterst{\"u}tzt die zuk{\"u}nftige Entwicklung von Wirkstoffen gegen das Tumorwachstum auf Basis der anti-invasiven Therapie.}, language = {de} } @phdthesis{Chatzidimitriou2005, author = {Chatzidimitriou, Nikolaos}, title = {Wird die Behandlung des kindlichen Hydrocephalus durch neue Ventilsysteme verbessert? Ein Vergleich zweier Shuntsysteme}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-13140}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2005}, abstract = {Der Unishunt der Firma Codman gilt als Niederdruck-System und f{\"u}hrt in aufrechter K{\"o}rperposition zur erheblichen {\"U}berdrainage. Das Delta-System der Firma Medtronic hingegen soll durch seinen Ventilmechanismus eine {\"U}berdrainage verhindern und den Liquordruck in einem physiologischen Rahmen halten. Die vorliegende Studie untersucht die Frage, ob das Delta-System gegen{\"u}ber dem Unishunt einen Vorteil hinsichtlich der {\"U}berdrainage aufweist, der sich an der revisionsfreien Funktionsdauer zeigt. Unter Ber{\"u}cksichtigung der Ventrikelweite pr{\"u}ften wir insbesondere, ob die {\"U}berdrainage und die damit verbundenen Komplikationen verringert werden k{\"o}nnen. In einer retrospektiven Fall-Sammel-Studie wurden die Patientendaten von 199 Kindern im Alter zwischen einem Tag und 10.4 Jahren ausgewertet, die im Zeitraum vom 01.01.1985 bis 01.03.2002 in der Abteilung f{\"u}r p{\"a}diatrische Neurochirurgie der Universit{\"a}tsklinik W{\"u}rzburg eine Erstimplantation eines ventrikuloperitonealen oder -atrialen Shunts mit Verwendung eines Unishunts (n= 138) oder eines Delta-Systems (n=61) erhielten. Gewertet wurden alle mechanischen oder infekti{\"o}sen Komplikationen, die zu einer operativen Shuntrevision f{\"u}hrten. Bei den mechanischen Komplikationen unterschieden wir zwischen proximaler Obstruktion, distaler Obstruktion, Migration, Diskonnektion oder Katheterriss, Ventilunterfunktion und {\"U}berdrainage. Als {\"U}berdrainage wurden operationspflichtige Subduralerg{\"u}sse, eindeutige Unterdruck-beschwerden und das Slit-Ventricle-Syndrom gewertet. Asymptomatische Subdural-erg{\"u}sse und andere nicht operationspflichtige Funktionsanomalien werteten wir nicht als Komplikation. Als Shuntinfektion bezeichneten wir klinische und laborchemische Zeichen einer bakteriellen Infektion, die nach Shuntexplantation abklangen. Die durchschnittliche Funktionsdauer der Shunts wurde in vorliegender Studie durch das Delta-System nicht verl{\"a}ngert. Die kumulative Revisionswahrscheinlichkeit nach einem Jahr betrug beim Unishunt 30.6 \%, beim Delta-System 24.9 \%, lag aber nach f{\"u}nf Jahren mit 58.0 \% beim Delta-System h{\"o}her als beim Unishunt (40.9 \%). Bei den mechanischen Komplikationen ergab sich als wesentlicher Unterschied zwischen beiden getesteten Systemen eine h{\"a}ufigere distale Blockade des Peritonealkatheters beim Unishunt, die aber durch h{\"a}ufigere Ventilfehlfunktion des Delta-Systems weitgehend ausgeglichen wurde. Die niedrigste Druckstufe f{\"u}hrte beim Delta-System signifikant h{\"a}ufiger zu einer proximalen Obstruktion als die h{\"o}chste. Die eigenen Untersuchungsergebnisse sprechen daf{\"u}r, dass Delta-Ventile tats{\"a}chlich der Neigung zur {\"U}berdrainage entgegenwirken, ohne dass sich dieser Vorteil in der Revisionsrate bemerkbar macht. Das Delta-System f{\"u}hrt zu einer niedrigeren {\"U}berdrainagerate und weniger {\"U}berdrainage-assoziierten Erscheinungen wie Subduralerg{\"u}ssen. Dieser Unterschied war am ehesten morphologisch zu erfassen, jedoch im Vergleich zum Unishunt nicht signifikant. Der Unishunt war mit einer h{\"o}heren Infektionsrate von 11.6 \% im Vergleich zum Delta-System (3.3 \%) belastet. Der Unterschied l{\"a}sst sich weder mit konstruktiven Ventilmerkmalen noch mit besonderen Maßnahmen der Infektionsprophylaxe erkl{\"a}ren. Der im Vergleich zum Unishunt h{\"o}here Preis des Delta-Systems findet keinen Niederschlag in einer niedrigeren Komplikationsrate des Systems.}, language = {de} } @phdthesis{Dette2007, author = {Dette, Katharina Gerda}, title = {Wirkung der Antibiotika Doxycyclin und Cefotaxim auf die MMP-Expression, sowie Proliferation, Adh{\"a}sion, Migration und Invasion bei Glioblastomzelllinien}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-25503}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2007}, abstract = {Das Glioblastom ist der h{\"a}ufigste prim{\"a}re maligne Hirntomor. Es zeichnet sich durch ein besonders aggessives und invasives Wachstumsverhalten aus. So konnte bis heute trotz moderner Diagnostik und Entwicklung neuer Behandlungsstrategien bestehend aus Operation, Radiatio und Chemotherapie mit Temozolamid die mittlere {\"U}berlebenszeit von 14.6 Monaten nicht {\"u}berschritten werden. Matrixmetalloproteinasen sind zinkabh{\"a}ngige Endopeptidasen, die in der Lage sind die Extrazellul{\"a}rmatrix zu degradieren, die Basalmembran zu durchbrechen, und somit Migration, Invasion, und Neovaskularisierung von Tumoren zu erleichtern. In zahlreichen Tumoren, so auch im Glioblastom, konnte eine {\"U}berexpression von MMPs, besonders von MMP2 und MMP9, nachgewiesen werden. Verschiedene Substanzen sind in der Lage, auf unterschiedlichen Ebenen die MMP-Synthese zu hemmen. Vor allem Doxycyclin, ein Antibiotikum aus der Gruppe der Tetracycline, sowie COL-3, ein chemisch modifiziertes Tetracyclinderivat, wurden an vielen Tumorentit{\"a}ten in pr{\"a}klinischen und klinischen Studien erfolgreich eingesetzt. Im Rahmen dieser Arbeit wurden 2 Antibiotika, Doxycyclin und Cefotaxim, auf ihre Wirkung auf 4 Gliomzelllinien, C6, U251, U373 und GaMG, sowie 4 Prim{\"a}rzellen, 2406, 2418, 2421 und 2464, untersucht. Sowohl Doxycyclin, als auch Cefotaxim hemmen teilweise die Expression von MMP2 und MMP9, was durch eine semiquantitative PCR nachgewiesen wurde; die Expression von TIMP1 bleibt weitgehend unver{\"a}ndert. Auch auf Proteinebene konnte mittels Immunhistochemie ein R{\"u}ckgang von MMP2 und MMP9 bei den meisten Zelllinien und Prim{\"a}rzellen unter Behandlung mit den Antibiotika beobachtet werden. Außerdem konnten Ver{\"a}nderungen im Wachstunsverhalten der Zellen in der Zellkultur verzeichnet werden, wahrscheinlich durch Inhibition der MMPs bedingt. Bei allen Zelllinien und allen Prim{\"a}rzellen wurde eine Abnahme der Proliferation im MTT-Assay, eine Zunahme der Adh{\"a}sion im Amidoblackassay, eine Abnahme der Migration im Migrationsassay, und eine Abnahme der Invasion im 3-D-Kollagengel-Assay beobachtet werden. Die Ergebnisse dieser Arbeit best{\"a}tigten die Resultate anderer Arbeitsgruppen mit Doxycyclin an anderen Tumoren, wie dem Prostata-Ca. Der deutliche Einfluss des Doxycyclins auf grundlegende Zelleigenschaften, wie z.B. dem Migrations-, Proliferations- und Invasionsverhalten, erfordert einen kritischen Umgang mit dem Tet-On/Off Systems zur Genregulation, insbesondere dann, wenn funktionelle Untersuchungen Teil der Versuchszielsetzung sind.}, subject = {Doxycyclin}, language = {de} } @phdthesis{Wess2008, author = {Wess, Christian}, title = {Wertigkeit der simultanen intraoperativen Ableitung von subduralem EEG und SSEP w{\"a}hrend vaskul{\"a}rer neurochirurgischer Operationen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-34855}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2008}, abstract = {Einleitung: SSEP sind etabliert, um Patienten intraoperativ zu {\"u}berwachen, wenn sie sich Operationen im zerebrovaskul{\"a}ren System unterziehen. Das EEG ist eine weitere Methode zur neurophysiologischen {\"U}berwachung. In dieser Studie wurde die Wertigkeit des simultanen Ableitens von SSEP und EEG Signalen untersucht. Methode: Dreizehn Patienten (7 Frauen, 6 M{\"a}nner, mittleres Alter 53.5 Jahre), welche sich dem Clipping eines intrakraniellen Aneurysma unterzogen, wurden eingeschlossen. Die SSEP Latenz 1 (Lat1), Latenz 2 (Lat2) und Amplitude (Amp) wurden kontinuierlich gemessen. Verminderung der Amplitude > 50\% oder Verl{\"a}ngerungen der Latenzen > 10\% gegen{\"u}ber den Ausgangswerten wurden als signifikante Ereignisse bewertet. Das EEG wurde mittels einer subduralen Grid-Elektrode gemessen. Alpha \% (Al\%), Alpha-Delta-Ratio (ADR) und Total Power (TP) wurden ausgewertet. Resultate: Circa 9000 Einzelwerte wurden analysiert. Statistisch signifikante Korrelationen traten zwischen Al\% und Amp (K=0.5) auf. Dabei zeigten sich die Ver{\"a}nderungen im EEG (Al\%) 6 Minuten vor Ereignissen im SSEP (Amp). Statistisch signifikante Korrelationen traten ebenfalls zwischen Al\% und Amp-Ereignissen (K=-0.4) auf. In 6/7 Patienten traten die Al\%-{\"A}nderungen 7 Minuten vor den Amp-{\"A}nderungen auf. Noch st{\"a}rkere Beziehungen ergaben sich zwischen Lat2 und allen EEG Modalit{\"a}ten, jedoch reichte die Gesamtzahl der Datenpunkte nicht aus, um statistische Signifikanzen herzuleiten. Schlussfolgerung: Dies ist die erste Beschreibung von signifikanten Beziehungen zwischen quantitativem SSEP und EEG w{\"a}hrend zerebrovaskul{\"a}ren Operationen. Das quantitative EEG hat das Potenzial, fr{\"u}he isch{\"a}mische Ereignisse eher zu detektieren als dies mit SSEP m{\"o}glich ist.}, subject = {intraoperatives Monitoring}, language = {de} } @phdthesis{Koehler2008, author = {K{\"o}hler, Stefan}, title = {Ophthalmologische und radiologische Hirndruckzeichen bei der isolierten Sagittalnahtsynostose}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-34666}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2008}, abstract = {Bei der h{\"a}ufigsten Form pr{\"a}maturer Kraniosynostosen, der isolierten Sagittalnahtsynostose, wird das Gesundheitsrisiko durch intrakranielle Drucksteigerung als sehr gering eingesch{\"a}tzt. Ziel der vorliegenden Studie war es, an einem gr{\"o}ßeren Kollektiv das individuelle Risiko einer Hirndrucksteigerung durch mangelhaftes Sch{\"a}delwachstum (=Kraniostenose) zu bestimmen. Der erh{\"o}hte Druck wurde dabei identifiziert durch Stauungspapillen oder durch direkte Messung. In einer L{\"a}ngsschnittstudie wurden Augenhintergrundsbefunde von 200 Patienten ausgewertet, die der W{\"u}rzburger kraniofazialen Arbeitsgruppe mit der klinischen Diagnose „isolierte Sagittalnahtsynostose" vorgestellt worden waren. Die bei acht Patienten durchgef{\"u}hrten direkten Druckmessungen wurden ebenfalls ausgewertet. Alle in die Studie aufgenommenen Patienten wurden mindestens einmal in zwei Jahren, in 76\% der F{\"a}lle entsprechend einer vorgegebenen Empfehlung zweimal j{\"a}hrlich ophthalmoskopisch untersucht. Zum Zeitpunkt der ersten Untersuchung waren die Kinder durchschnittlich 14 Monate, bei der letzten Untersuchung durchschnittlich sieben Jahre alt. Die Beobachtungsdauer lag zwischen 19 Monaten und 18 Jahren. W{\"a}hrend der Beobachtungszeit entwickelten zehn Patienten eine sichere Hirndrucksteigerung nach der genannten Definition, drei von 71 nicht operierten Patienten und sieben von 129 operativ behandelten Kindern. Daraus errechnete sich ein kumulatives individuelles Risiko von knapp sechs Prozent im Spontanverlauf und knapp sieben Prozent nach vorangegangener Operation. Diese Zahlen waren aber durch diagnostische Irrt{\"u}mer beeinflusst. Denn bei sechs der 200 Patienten musste die Diagnose im Verlauf zugunsten verschiedener Syndrome und Stoffwechselst{\"o}rungen korrigiert werden. Drei dieser Patienten hatten Stauungspapillen entwickelt. Nach entsprechender Bereinigung des Studienkolletivs lag das individuelle Risiko einer Hirndrucksteigerung f{\"u}r nicht operierte Patienten mit isolierter Sagittalnahtsynostose bei drei Prozent, f{\"u}r operierte Patienten bei sechs Prozent. Bei zwei Patienten wurde die Hirndrucksteigerung durch direkte Messung nachgewiesen, w{\"a}hrend der Augenhintergrund unauff{\"a}llig erschien - ein Hinweis auf die relativ geringe Sensitivit{\"a}t des ophthalmoskopischen Befundes. Aus den vorliegenden Daten ergibt sich die Empfehlung regelm{\"a}ßiger Funduskontrollen bei der isolierten Sagittalnahtsynostose, die unbedingt auch nach einer Operation der Synostose bis mindestens zum achten, besser bis zum 10. bis 12. Lebensjahr fortgesetzt werden sollten. Untersuchungsintervalle von sechs Monaten stellen dabei einen vertretbaren Kompromiss zwischen Untersuchungsaufwand und diagnostischer Sicherheit dar. Denn alle Patienten mit Stauungspapillen wurden rechtzeitig therapiert, keiner von ihnen erlitt bleibende Funktionseinbußen der Sehnerven. Wegen der geringen Sensitivit{\"a}t der Ophthalmoskopie wurden in einem zweiten Teil der Arbeit R{\"o}ntgenaufnahmen der Patienten auf radiologische Hirndruckzeichen ausgewertet. Das Sch{\"a}delinnenrelief wurde beurteilt und in Anlehnung an die Literatur in drei Intensit{\"a}tsgrade eingeteilt. Deutlich und generalisiert verst{\"a}rkte Impressiones digitatae im Sinne eines Wolkensch{\"a}dels wurden als m{\"o}gliche Zeichen eines erh{\"o}hten intrakraniellen Drucks registriert. Am Ende des Beobachtungszeitraums wurde sowohl bei operierten als auch bei nicht operierten Patienten eine kumulative Wahrscheinlichkeit f{\"u}r das Auftreten eines Wolkensch{\"a}dels von etwa 35\% ermittelt, bei allerdings hoher statistischer Un¬genauigkeit. Insgesamt wurde bei 20\% der nicht operierten und bei 15\% der operierten Patienten ein Wolkensch{\"a}del registriert. In Zusammenschau mit den Ergebnissen des ersten Teils der Arbeit st{\"u}tzen diese Zahlen die Annahme, dass eine intrakranielle Drucksteigerung h{\"a}ufiger auftritt als funduskopisch nachgewiesen. Bei deutlich verst{\"a}rktem Sch{\"a}delinnenrelief im R{\"o}ntgenbild sollte daher die Indikation zur invasiven Druckmessung großz{\"u}giger gestellt werden. Als {\"u}berraschendes und bisher nicht beschriebenes Ergebnis ließ sich ein {\"U}bergreifen der Synostose auf weitere N{\"a}hte kumulativ bei 20\% der operierten, nicht aber bei unoperierten Patienten nachweisen. Diese Beobachtung steht im Einklang mit der gr{\"o}ßeren H{\"a}ufigkeit von Stauungspapillen im postoperativen Verlauf. Denkbar ist also eine negative Beeinflussung der Nahtphysiologie durch die Operation.}, subject = {Hirndruck}, language = {de} } @phdthesis{Eskandar2008, author = {Eskandar, Kevin}, title = {Langzeitdepressions-{\"a}hnliche Minderung kortikospinaler Exzitabilit{\"a}t durch ein assoziatives Paarstimulationsprotokoll : Methodische Untersuchungen und neurophysiologisches Mapping}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-36245}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2008}, abstract = {Neuronale Plastizit{\"a}t ist die Voraussetzung f{\"u}r Lernen und Erinnerung. Sie wurde in einer Reihe von Experimenten am Menschen und am Tier eindrucksvoll demonstriert. Das zugrunde liegende Prinzip neuronaler Plastizit{\"a}t ist die Modulierbarkeit synaptischer {\"U}bertragungseffizienz. Diese kann im Sinne einer Langzeitpotenzierung (LTP) sowohl hinauf als auch im Sinne einer Langzeitdepression (LTD) herab reguliert werden. Von besonderem Interesse im Allgemeinen und f{\"u}r diese Arbeit ist das Prinzip der assoziativen LTD: Wirkt auf das postsynaptische Neuron zun{\"a}chst ein starker depolarisierender Reiz und danach in enger zeitlicher Kopplung ein schwacher nicht depolarisierender Reiz so kommt es in der Folge zu einer Erniedrigung der synaptischen {\"U}bertragungseffizienz. F{\"u}r den menschlichen Motorkortex wurde ein experimentelles Protokoll entwickelt, dass mit Hilfe etablierter neurophysiologischer Methoden eine Ver{\"a}nderung der synaptischen {\"U}bertragungseffizienz im Sinne eines LTD-{\"a}hnlichen Ph{\"a}nomens bewirkt: beinahe synchrone und repetitive Kopplung peripherer N. medianus Stimulation (entspricht dem nicht depolarisierenden Reiz) und kontralateraler transkranieller Magnetstimulation (entspricht dem depolarisierenden Reiz) f{\"u}hrt zu einer signifikanten Amplitudenreduktion der magnetisch evozierbaren Potentiale (MEP) des M. abductor pollicis brevis (APB). Voraussetzung f{\"u}r die Effektivit{\"a}t der assoziativen Paarstimulation (PAS-Protokoll) ist, dass der depolarisierende Reiz wenige Millisekunden vor dem nicht depolarisierenden Reiz auf die synaptischen Verbindungen des zentralen APB-Repr{\"a}sentationsareals einwirkt. Das Ziel dieser Arbeit war es zun{\"a}chst durch Optimierung der im PAS-Protokoll etablierten Stimulationsparameter die Robustheit und das Ausmaß der erzeugten Exzitabilit{\"a}tsminderung im APB-Kortexareals zu steigern. Untersucht wurde erstens der Einfluss der Steigerung der Frequenz, sowie zweitens der absoluten Zahl applizierter Paarreize. Drittens wurde untersucht ob ein optimaler Wirkzeitabstand zwischen den beiden assoziativen Stimuli besteht: Eine Synchronisierung des Intervalls zwischen den beiden Paarreizen durch Normierung auf die individuelle K{\"o}rperl{\"a}nge f{\"u}hrt zu einem konstanten Wirkzeitabstand innerhalb der synaptischen Verbindungen des zentralen APB-Repr{\"a}sentationsareales. Dies erlaubt eine systematische Untersuchung des optimalen Wirkzeitabstandes der assoziativen Paarreize unabh{\"a}ngig von der individuellen K{\"o}rperl{\"a}nge. Mit einem so optimierten PAS-Protokoll wurde der zweite Teil der Arbeit durchgef{\"u}hrt: In den eben beschriebenen Vorversuchen wurde die {\"A}nderung der kortikomuskul{\"a}ren Exzitabilit{\"a}t durch Vergleich der durchschnittlichen MEP-Amplituden des Punktes der Sch{\"a}deldecke, von dem aus eine maximale Reizantwort im Zielmuskel erzeugbar war bestimmt. Um jedoch eine m{\"o}glichst umfassende Aussage {\"u}ber die Ver{\"a}nderung kortikomuskul{\"a}rer Exzitabilit{\"a}t treffen zu k{\"o}nnen, wurde ein etabliertes Kartierungsverfahren verwendet, das eine Darstellung des APB-Repr{\"a}sentationsareales als zweidimensionale Karte erm{\"o}glicht. Mit Hilfe dieser Mapping-Untersuchung sind Aussagen {\"u}ber die r{\"a}umliche Dimension der Ver{\"a}nderungen kortikomuskul{\"a}rer Exzitabilit{\"a}t m{\"o}glich, die {\"u}ber den einfachen Vergleich der an einem Punkt gewonnenen Amplituden hinausgehen. In dieser Arbeit gelang die Induktion kortikaler Plastizit{\"a}t im Sinne assoziativer LTD-{\"a}hnlicher Plastizit{\"a}t. Aus unseren Ergebnissen l{\"a}sst sich ableiten, dass weder durch eine Erh{\"o}hung der Frequenz noch der Anzahl der Paarstimuli eine wesentliche Steigerung des LTD-{\"a}hnlichen Ph{\"a}nomens zu erzeugen ist. Diesen Umstand f{\"u}hren wir im Wesentlichen auf eine Art Grenzwert der Modulierbarkeit kortikomuskul{\"a}rer Exzitabilit{\"a}t zur{\"u}ck. Die grunds{\"a}tzliche M{\"o}glichkeit, dass mentale Konzentration auf die in das PAS-Protokoll involvierten Muskeln eine bedeutsamere Rolle f{\"u}r das Ausmaß der induzierten Plastizit{\"a}t spielen k{\"o}nnte als die Intensit{\"a}t der assoziativen Induktion, wurde er{\"o}rtert. Durch einen Normierungsprozess auf die individuelle K{\"o}rpergr{\"o}ße kristallisiert sich ein definiertes Fenster der zeitlichen Kopplung der beiden assoziativen Reize mit optimaler LTD-{\"a}hnlicher Plastizit{\"a}t heraus. Bei selektiver Betrachtung einer Subgruppe der Mapping-Untersuchung ergaben sich Hinweise darauf, dass die r{\"a}umliche Verteilung der Exzitabilit{\"a}t durch ein optimiertes PAS-Protokoll ver{\"a}ndert wird. Diese Hinweise sind mit der Annahme zu vereinbaren, dass durch ein exzitabilit{\"a}tsminderndes PAS-Protokoll aktive Synapsen deaktiviert werden k{\"o}nnen. M{\"o}gliche Ursachen f{\"u}r die vergleichsweise schlechte Reproduzierbarkeit der Plastizit{\"a}tsergebnisse bei kumulativer Betrachtung aller Mapping-Experimente wurden diskutiert.}, subject = {Mapping }, language = {de} } @phdthesis{Kessler2009, author = {Keßler, Almuth Friederike}, title = {Der Proteasomenaktivator PA28gamma bei der Tumorentstehung und seine Verbindung zur Stresssignalgebung und zur Zellzyklusregulation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-74469}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2009}, abstract = {Das Glioblastom ist der h{\"a}ufigste hirneigene Tumor des Erwachsenen. Es ist hoch invasiv, stark proliferierend und mit einer schlechten Prognose assoziiert. Heutige Therapiean-s{\"a}tze zielen, neben der m{\"o}glichst vollst{\"a}ndigen Resektion des Tumorgewebes, vor allem auf Apoptoseinduktion durch DNA-Sch{\"a}den in Tumorzellen. Daher ist die Aufkl{\"a}rung der molekularen Grundlagen dieser Prozesse essentiell, um Verbesserungen bei den Behandlungsm{\"o}glichkeiten erzielen zu k{\"o}nnen. Der Proteasomenaktivator PA28γ wird im Hirngewebe stark exprimiert, {\"u}ber seine Funktion ist jedoch nur wenig bekannt. Er wurde als Interaktionspartner des Zellzyklus- und DNA-Schadensregulators Mad2b in einem Hefe Two-Hybrid Screen identifiziert. Im Rahmen dieser Arbeit wurde diese Wechselwirkung mittels eines GST-Pulldown Experimentes be-st{\"a}tigt. Obwohl PA28γ in Verbindung mit der Zellproliferation gebracht wird, konnte in GBM-Zelllinien keine signifikante {\"A}nderung der Zellteilungsraten beobachtet werden. Allerdings unterst{\"u}tzte die vermehrte Expression von PA28γ die Apoptose. Um durch neue Interaktionspartner von PA28γ Hinweise auf dessen Funktion zu erhalten, wurde ein Hefe Two-Hybrid Screen durchgef{\"u}hrt: PA28gamma steuert den Abbau von p53 und verweist {\"u}ber die hier neu beschriebene Interaktion mit HIPK1 ebenfalls auf den programmierten Zelltod. Dieser pro-apoptotische Zusammen-hang wird unterst{\"u}tzt durch die Interaktion mit 1A6/DRIM-interacting protein. Die Inter-aktion der Sumo E2 Ligase Ubc9 mit PA28gamma war ein erster Hinweis f{\"u}r eine Sumoylierung des Proteasomenaktivators, die die PA28gamma Aktivit{\"a}t regulieren k{\"o}nnte. Gleichzeitig ist Ubc9, wie auch die E3-Ligase PIAS, im Zusammenhang mit Apoptose beschrieben worden. Diese Fragestellungen wurden in weiterf{\"u}hrenden Arbeiten erforscht. Einen anderen Aspekt beleuchtet die Interaktion von PA28gammamit Catenin alpha. Durch diese Wechselwirkung k{\"o}nnte PA28gamma Einfluß auf Interzellul{\"a}rkontakte nehmen. Gerade im Hin-blick auf das GBM, charakterisiert durch ausgepr{\"a}gtes Migrations- und Invasionsverhal-ten, k{\"o}nnte die Regulation von Interzellul{\"a}rkontakten von besonderer Bedeutung sein. Aufgrund der oben beschriebenen Eigenschaften von PA28gammasollte dieses Protein f{\"u}r eine Therapie mittels DNA-Sch{\"a}den induzierter Apoptose erforscht werden. PA28gamma k{\"o}nnte bei diesen Vorg{\"a}ngen ein zentraler Faktor sein, dessen Manipulation die etablierten Therapieformen unterst{\"u}tzen und deren Wirkung verbessern.}, subject = {Proteasomenaktivator}, language = {de} } @phdthesis{Rogausch2009, author = {Rogausch, Jan Philipp}, title = {Systemische Zytokinexpression bei schmerzhaften und schmerzlosen Polyneuropathien}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-37522}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2009}, abstract = {Bislang ist ungekl{\"a}rt, warum PNPs teils schmerzhaft und teils schmerzlos verlaufen. Die in der vorliegenden Arbeit untersuchte Hypothese lautete, dass ein Ungleichgewicht zwischen pro- und anti-inflammatorischen Zytokinen der unterschiedlichen Schmerzauspr{\"a}gung zugrunde liegt.Es wurden 32 Patienten mit schmerzhafter PNP, 20 Patienten mit schmerzloser PNP und 44 Kontrollpersonen auf die Expression und Produktion ausgew{\"a}hlter pro- und anti-inflammatorischer Zytokine untersucht. Zur Messung der Schmerzhaftigkeit wurden etablierte Schmerzfrageb{\"o}gen verwendet. Zus{\"a}tzlich wurden nahezu alle Patienten mit der Allgemeinen Depressionsskala befragt. Die Diagnose, {\"A}tiologie, Dauer, klinische Manifestation der PNP sowie die Medikation der Patienten wurde auf standardisierten Erhebungsb{\"o}gen dokumentiert. Zur Messung der Zytokine wurde morgens Blut in EDTA- und Serummonovetten asserviert und entsprechend der Messmethodik weiterverarbeitet. Die relative Genexpression wurde aus Gesamt-RNA mittels reverser Transkription und quantitativer real-time PCR, die Serumproteine mittels enzyme-linked immunosorbant assay gemessen. Die Patienten mit schmerzhafter PNP hatten in der Mehrzahl Neuropathie-typische Plussymptome und mittelstarke Schmerzen, die eine starke bis sehr starke Behinderung darstellten. Die hier untersuchten Zytokinmuster bei Patienten mit schmerzhafter und schmerzloser PNP zeigten eine Verschiebung zu pro-inflammatorischen Zytokinen bei Patienten mit schmerzhafter PNP. Die Zytokinexpression der Patienten mit schmerzhafter PNP war im Vergleich zu Patienten mit schmerzloser PNP und Kontrollen bez{\"u}glich der IL-2 und TNF Expression und Produktion signifikant erh{\"o}ht. Umgekehrt lagen bei Patienten mit schmerzloser PNP die Produktion und die Expression des IL-4 im Vergleich zu Patienten mit schmerzhafter PNP und Kontrollen h{\"o}her. Die Expression des IL-10 lag bei Patienten mit schmerzloser PNP ebenfalls h{\"o}her als bei Patienten mit schmerzloser PNP und Kontrollen, unterschied sich aber auf Proteinebene nicht in den drei Gruppen. Die einleitend gestellte Hypothese, dass der schmerzhafte oder schmerzlose Verlauf einer PNP durch unterschiedliche Zytokinprofile bedingt ist, kann durch die vorliegenden Ergebnisse gest{\"u}tzt werden. In Zusammenschau mit den Daten aus der Grundlagenforschung scheint einem pro-inflammatorischen Zytokinmuster eine entscheidende Rolle an der Entstehung und Aufrechterhaltung neuropathischer Schmerzen zuzukommen. F{\"u}r TNF sind entsprechende pathophysiologische Wirkungen bekannt. Anti-inflammatorische Zytokine, wie IL-4 und IL-10 zeigten analgetische Wirkungen im Tierversuch. Die Mitwirkung des IL-2 an peripheren Opioid-Rezeptoren l{\"a}sst eine endogene periphere Analgesie vermuten. Hieraus lassen sich Folgerungen f{\"u}r zuk{\"u}nftige Diagnostik und Therapie neuropathischer Schmerzen ziehen. Durch Erkennung von Zytokin-Imbalancen w{\"a}ren schmerzhafte PNPs fr{\"u}her einer ad{\"a}quaten Therapie zuzuf{\"u}hren. Durch die Modulation von Zytokinprofilen im Rahmen schmerzhafter PNPs k{\"o}nnten sich zus{\"a}tzlich therapeutische M{\"o}glichkeiten er{\"o}ffnen.}, subject = {Cytokine}, language = {de} } @article{AlbertWeissenbergerSiren2010, author = {Albert-Weissenberger, Christiane and Sir{\´e}n, Anna-Leena}, title = {Experimental traumatic brain injury}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68131}, year = {2010}, abstract = {Traumatic brain injury, a leading cause of death and disability, is a result of an outside force causing mechanical disruption of brain tissue and delayed pathogenic events which collectively exacerbate the injury. These pathogenic injury processes are poorly understood and accordingly no effective neuroprotective treatment is available so far. Experimental models are essential for further clarification of the highly complex pathology of traumatic brain injury towards the development of novel treatments. Among the rodent models of traumatic brain injury the most commonly used are the weight-drop, the fluid percussion, and the cortical contusion injury models. As the entire spectrum of events that might occur in traumatic brain injury cannot be covered by one single rodent model, the design and choice of a specific model represents a major challenge for neuroscientists. This review summarizes and evaluates the strengths and weaknesses of the currently available rodent models for traumatic brain injury.}, subject = {Trauma}, language = {en} } @phdthesis{Schoemig2010, author = {Sch{\"o}mig, Beate}, title = {Regulation tumorassoziierter Proteine in humanen Gliomen durch den Einfluss von Hypoxie}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-49347}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2010}, abstract = {Das Glioblastom ist mit einem Anteil von 20\% an allen hirneigenen Tumoren der h{\"a}ufigste und b{\"o}sartigste prim{\"a}re intrakranielle Tumor. Trotz multimodalem Therapiekonzept, das operative Resektion, Strahlen- und Chemotherapie verbindet, haben Patienten eine Prognose von im Mittel nur 14,6 Monaten. Sein aggressives Wachstum zieht eine Vaskularisierung nach sich, die jedoch nicht in ausreichendem Maße die Sauerstoffversorgung des Tumorgewebes sicherstellen kann. Studien mit Messelektroden zeigten einen deutlich reduzierten Sauerstoffpartialdruck im Tumor im Vergleich zum umliegenden Hirngewebe. Dieses hypoxische Milieu l{\"o}st genetische Alterationen und adaptive Ver{\"a}nderungen der Proteinexpression aus, die eine Selektion besonders aggressiver Tumorzellen bewirkt. F{\"u}r eine bessere prognostische Einsch{\"a}tzung sowie als zuk{\"u}nftige therapeutische Ziele zur Erh{\"o}hung der Response auf Chemo- und Strahlentherapie ist es von großem Interesse, solche Faktoren als m{\"o}gliche Hypoxiemarker aufzufinden. In dieser Arbeit wurden die Proteine HIF-1\&\#945;, CAIX, VEGF, EPO und NDRG1 auf mRNA- und Proteinebene in den Glioblastomzelllinien GaMG, U251 und U373 auf eine Ver{\"a}nderung ihrer Expression unter hypoxischen Bedingungen untersucht. Ausmaß (5\% O2, 1\% O2 und 0,1\% O2) und Dauer (1 h, 6 h und 24 h) der Hypoxie wurde variiert. Anschließend wurde {\"u}ber 24 h und 48 h eine Reoxygenierung durchgef{\"u}hrt. Auch wurden Expressionsuntersuchungen an Gewebeproben von Normalhirnen, Astrozytomen WHO Grad II und Glioblastomen vorgenommen. Die Verwendbarkeit von GAPDH als Marker f{\"u}r diese Analysen wurde durch Experimente sichergestellt, die dessen mRNA und das Protein als nicht durch Hypoxie oder Malignisierung reguliert nachwiesen. Wir best{\"a}tigten die Rolle von HIF-1\&\#945; als Mediator der hypoxischen Zellantwort. W{\"a}hrend die mRNA konstant blieb, wurde das Protein unter hypoxischen Bedingungen hochreguliert. Dies zeigte auch, dass unser experimentelles Setting funktionierte. NDRG1, CA-IX sowie EPO wurden unter Hypoxie sowohl auf mRNA-, als auch Proteinebene hochreguliert und blieben unter Reooxygenierung stabil. In Glioblastomen waren diese Gene auf mRNA-Ebene bedeutend st{\"a}rker exprimiert als in niedriggradigen Astrozytomen. HIF-1\&\#945;, NDRG1, CA-IX sowie EPO k{\"o}nnen also in humanen Glioblastomzellen als Hypoxiemarker dienen und m{\"o}glicherweise auch eine prognostische und therapeutische Bedeutung haben.}, subject = {Hypoxie}, language = {de} } @phdthesis{Linsenmann2010, author = {Linsenmann, Thomas}, title = {Das neonatale Kraniopharyngeom - Ein kasuistischer Beitrag und Literatur{\"u}bersicht}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-49757}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2010}, abstract = {Das Kraniopharyngeom ist eine dysontogenetische Mittellinienfehlbildung mit raumforderndem Charakter. Die {\"A}tiopathogenese ist noch ungekl{\"a}rt. Bildgebende Verfahren (Sonographie, MRT) erm{\"o}glichen bereits pr{\"a}natal eine Diagnostik. Das neonatale Kraniopharyngeom ist sehr selten. Bisher finden sich in der Literatur nur wenige Fallberichte von denen operative Verl{\"a}ufe sowie klinische Langzeitverl{\"a}ufe bekannt sind. Es bleibt eine Kontroverse hinsichtlich Radikalit{\"a}t und Zeitpunkt der Operation, nicht aber dahingehend, dass die operationsmikroskopische Versorgung die Therapie der Wahl des neonatalen Kraniopharyngeoms darstellt. Die N{\"a}he zur hypophys{\"a}ren-hypothalamischen Achse bedingt eine hohe Komorbidit{\"a}t der Kinder pr{\"a}- und postoperativ.}, subject = {Neurochirurgie}, language = {de} } @phdthesis{Kahle2010, author = {Kahle, Philipp}, title = {Resttumore bei der mikrochirurgischen Therapie von Vestibularschwannomen - funktionelle Ergebnisse und radiologisches Verhalten}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-52066}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2010}, abstract = {Einleitung: Zwischen 1994-2003 wurden in Zusammenarbeit von HNO- und Neurochirurgie 615 Vestibularschwannome (Grad T3a-T4b) {\"u}ber den subokzipitalen Zugang operiert. In 89 F{\"a}llen (14\%) konnte aus unterschiedlichen Gr{\"u}nden der Tumor nur inkomplett entfernt werden. Mittels neurologischer Untersuchung und MRT wurde postoperativ das funktionelle Ergebnis bzw. das Wachstumsverhalten des Resttumors untersucht. Außerdem wurden die Art des Resttumors und die Gr{\"u}nde f{\"u}r eine inkomplette Resektion analysiert. Material und Methoden: Alle Tumore wurden unter stetigem Neuromonitoring (AEP, Fazialis-EMG) operiert. Reichte der Tumor bis an die kaudalen Hirnnerven (IX, X, XI, XII) heran, wurden diese ebenfalls {\"u}berwacht. In der postoperativen Kontrolle erfolgten eine neurologische Untersuchung und eine MRT. Die Ergebnisse wurden mit vorausgegangenen Untersuchungen verglichen, um das Wachstumsverhalten des Resttumors und das funktionelle Ergebnis zu beurteilen. Die Operationsberichte wurden nach den Gr{\"u}nden der inkompletten Tumorentfernung gesichtet. Ergebnisse: Starke Adh{\"a}renz des Tumorgewebes zu den Hirnnerven (VII, VIII, kaudale Gruppe) oder zum Hirnstamm, interfaszikul{\"a}re Tumornester, eine Gef{\"a}hrdung der Blutversorgung, spontane Entladungen im EMG oder eine reduzierte Ableitbarkeit der AEPs zwangen den Operateur, die Pr{\"a}paration abzubrechen. Die durchschnittliche Tumorgr{\"o}ße in den F{\"a}llen der inkompletten Resektion betrug 26,8 mm vs. 19,4 mm bei kompletter Tumorentfernung. Der zur{\"u}ckgelassene Tumorrest bestand in 86\% aus einem Kapselanteil, einem Tumorrasen oder interfaszikul{\"a}ren Tumornestern. Grobe Tumorreste waren die Ausnahme. 12 Monate postoperativ wurde bei den Patienten mit kompletter Resektion in 88\% eine gute bis sehr gute Funktionalit{\"a}t (House/Brackmann Grad I-II) des Gesichtsnervs beobachtet, bei inkompletter Tumorentfernung in 75\%. 66\% (n=59) der Resttumore zeigten keine Progredienz, 13\% (n=12) eine Wachstumstendenz ohne klinische Symptomatik, 6\% (n=5) mussten erneut operiert werden (15\%/n=13 keine Kontrolle). Der durchschnittliche Nachbeobachtungszeitraum betrug 48,1 Monate (1-134). Zusammenfassung: Trotz Zur{\"u}cklassens eines Tumorrestes kommt es nur selten zu einem erneuten Tumorwachstum. In noch weniger F{\"a}llen muss eine Rezidivoperation durchgef{\"u}hrt werden. Dies rechtfertigt eine subtotale Tumorresektion in den F{\"a}llen einer Hirnnervengef{\"a}hrdung. Verzichtet man auf eine komplette Resektion, l{\"a}sst sich auch bei sehr großen Tumoren ein gutes bis sehr gutes funktionelles Ergebnis erzielen.}, subject = {Akustikustumor}, language = {de} } @phdthesis{Rascher2010, author = {Rascher, Alexandra}, title = {Critical-Illness-Polyneuropathie - Ergebnisse nach neurologisch-neurochirurgischer fr{\"u}hrehabilitativer Behandlung}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-51936}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2010}, abstract = {Die Critical-lllness-Polyneuropathie (CIP), eine Erkrankung des peripheren Nervensystems nach einer schweren intensivmedizinisch behandlungspflichtigen Erkrankung, ist bereits seit dem 19. Jahrhundert bekannt und l{\"a}sst sich nur sehr schwer von einer Critical-Illness- Myopathie, die im gleichen Kontext auftreten kann, unterscheiden. Erschwert wird die Situation dadurch, dass beide Funktionsst{\"o}rungen kombiniert auftreten k{\"o}nnen. Auf Grund der Weiterentwicklung in der Medizin ist in den letzten 2 Jahrzehnten eine H{\"a}ufigkeitssteigerung zu verzeichnen mit der Forderung geeignete Maßnahmen zu finden, die h{\"a}ufig schwerwiegenden Folgeerscheinungen zu mindern. Mit Entwicklung eines bestimmten neurorehabilitativen Behandlungsregimes ergeben sich die Fragen, welche CIP Patienten profitieren, ergeben sich prognoserelevante Faktoren und welche Art und Dauer der Neurorehabilitation vorgehalten werden muss. In der vorliegenden Arbeit wurden retrospektiv die Entlassungsbriefe der Patienten mit einer CIP der Abteilung f{\"u}r neurologisch-neurochirurgisch Fr{\"u}hrehabilitation der Jahre 2004-2008 ausgewertet. Die Beurteilung der F{\"a}higkeitsst{\"o}rungen erfolgte mit dem Fr{\"u}hrehabilitations-Barthel-Index nach Sch{\"o}nle, dem Barthel-Index sowie dem FIM und das Handicap wurde mit der 8-stufigen Glasgow-Outcome-Scale bewertet. Zus{\"a}tzliche Parameter waren das Alter und Geschlecht, die Ursache der CIP, die Zeit von Erkrankungsbeginn bis zur Aufnahme, die Behandlungsdauer, Komplikationen sowie die Entlassungsart. 200 Patienten, 67,5\% M{\"a}nner und 32,5\% Frauen konnten ausgewertet werden. Eine H{\"a}ufung des Erkrankungsbildes fand sich bei Patienten ab dem 60. Lebensjahr. Eine Ursachenpr{\"a}ferenz fand sich nicht, wobei im Wesentlichen kardiale, respiratorische und gastrointestinale Erkrankungen vorgefunden worden waren. Alle Patienten konnten, nach einer durchschnittlichen Behandlungsdauer von 40 Tagen, von der Fr{\"u}hrehabilitationsbehandlung profitieren. So konnten 34\% in weiterf{\"u}hrende rehabilitative Behandlungsstufen und 17,5\% der Patienten gebessert nach Hause entlassen werden. Die Sterblichkeit mit 11\% muss der besonderen Schwere des Krankheitsbildes angelastet werden. Dies wird durch die Feststellung gest{\"u}tzt, dass die Komplikationsrate mit {\"u}ber 60\% w{\"a}hrend der rehabilitativen Behandlung sehr hoch lag. Hervorzuheben ist, dass sich herausarbeiten ließ, dass sich eine l{\"a}ngere Behandlung positiv auf die Behandlungsergebnisse, auch bei schwer Betroffenen auswirkte. Die ausl{\"o}sende Ursache scheint keinen wesentlichen Einfluss auf das outcome zu haben. M{\"a}nner profitieren bei der Wiedererlangung motorischer F{\"a}higkeiten etwas besser als Frauen. Die {\"a}lteren Patienten zeigen gute Verbesserungen bei k{\"o}rperlichen Funktionsst{\"o}rungen. Bezogen auf die kognitiven F{\"a}higkeiten muss aber das Alter als negativer Pr{\"a}diktor angesehen werden. Der Grad der Behinderung hat einen deutlichen Einfluss auf die Behandlungsdauer und Behandlungsergebnisse. Demgegen{\"u}ber stellt eine prim{\"a}re Intensivpflicht einen negativen Pr{\"a}diktor, auch wenn auch diese Patienten von der Rehabilitation profitieren.}, subject = {cip}, language = {de} } @article{HagemannAnackerHaasetal.2010, author = {Hagemann, Carsten and Anacker, Jelena and Haas, Stefanie and Riesner, Daniela and Sch{\"o}mig, Beate and Ernestus, Ralf-Ingo and Vince, Giles H.}, title = {Comparative expression pattern of Matrix-Metalloproteinases in human glioblastoma cell-lines and primary cultures}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-67980}, year = {2010}, abstract = {Background: Glioblastomas (GBM), the most frequent malignant brain tumors in adults, are characterized by an aggressive local growth pattern and highly invasive tumor cells. This invasion is facilitated by expression of matrix metalloproteinases (MMPs), a family of zinc-dependent endopeptidases. They mediate the degradation of protein components of the extracellular matrix. Twenty-three family members are known. Elevated levels of several of them have been reported in GBM. GBM cell-lines are used for in vitro studies of cell migration and invasion. Therefore, it is essential to know their MMP expression patterns. Only limited data for some of the cell-lines are published, yet. To fill the gaps in our knowledge would help to choose suitable model systems for analysis of regulation and function of MMPs during GBM tumorigenesis, cell migration and invasion. Findings: We analysed MMP-1, -8, -9, -10, -11, -13, -17, -19, -20, -21, -23, -24, -26, -27, and MMP-28 expression in seven GBM cell-lines (SNB-19, GaMG, U251, U87, U373, U343, U138) and in four primary cell cultures by semiquantitative RT-PCR, followed changes in the MMP expression pattern with increasing passages of cell culture and examined the influence of TNF-a and TGF-b1 stimulation on the expression of selected MMPs in U251 and U373 cells. MMP-13, -17, -19 and -24 were expressed by all analyzed cell-lines, whereas MMP-20 and MMP-21 were not expressed by any of them. The other MMPs showed variable expression, which was dependent on passage number. Primary cells displayed a similar MMP-expression pattern as the cell-lines. In U251 and U373 cells expression of MMP-9 and MMP-19 was stimulated by TNF-a. MMP-1 mRNA expression was significantly increased in U373 cells, but not in U251 cells by this cytokine. Whereas TGF-b1 had no impact on MMP expression in U251 cells, it significantly induced MMP-11 and MMP-24 expression in U373 cells. Conclusions: Literature-data and our own results suggest that the expression pattern of MMPs is highly variable, dependent on the cell-line and the cell-culture conditions used and that also regulation of MMP expression by cytokines is cell-line dependent. This is of high impact for the transfer of cell-culture experiments to clinical implementation.}, subject = {Metalloproteinasen}, language = {en} } @phdthesis{Raslan2011, author = {Raslan, Furat}, title = {Pathomechanismen und Therapie der Kallikrein-Kinin-System vermittelten Hirn{\"o}dembildung nach Neurotrauma}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-71407}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {In einem experimentellen Sch{\"a}del-Hirn-Trauma-Modell der fokalen K{\"a}ltel{\"a}sion bei der Maus wurde die Effektivit{\"a}t der B1R-Blockade untersucht. Die Ergebnisse dieser Untersuchung dokumentierten auf der Suche nach einer grundlegenden spezifischen Therapie des vasogenen traumatischen Hirn{\"o}dems die B1R-Blockade als einen potentiellen Ansatz zu Reduktion der sekund{\"a}ren Hirn-sch{\"a}den. Zum Einen konnte durch die selektive Blockade von B1R mit dem Pr{\"a}parat R-715 nach einer fokalen K{\"a}ltel{\"a}sion im Mausmodell die Hirnsch{\"a}digung um etwa 75 \% gegen{\"u}ber den Tieren der Kontrollgruppen reduziert werden. Zum Anderen l{\"a}sst sich nach der B1R-Blockade u. a. eine signifikante Abschw{\"a}chung des vasogenen Hirn{\"o}dems um etwa 50 \% im Vergleich zu den Tieren der Kontrollgruppen feststellen. Die Reduktion der sekund{\"a}ren Hirnsch{\"a}digung durch die B1R-Blockade 24 Stunden nach der L{\"a}sionsinduktion macht die selektive B1R-Blockade als kausaler Therapie-ansatz eine interessante Behandlungsoption des posttraumatischen vasogenen Hirn{\"o}dems.}, subject = {Sch{\"a}del-Hirn-Trauma}, language = {de} } @phdthesis{Graulich2011, author = {Graulich, Michael}, title = {Spinale Effekte von TNF-α am Modell des tumorinduzierten Knochenschmerzes der Maus}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-54439}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Am Modell des tumorinduzierten Schmerzes der Maus wurden sowohl das Schmerzverhalten der Tiere als auch spezifische morphologische Ver{\"a}nderungen im Hinterhorn des R{\"u}ckenmarks (Aktivierung von Astrozyten) und im tumorbefallenen Knochen analysiert. Durch Analyse von M{\"a}usen mit Defizienz f{\"u}r TNF-Rezeptor 1, TNF-Rezeptor 2 oder f{\"u}r beide Rezeptoren konnte die Rolle von TNF-α seiner Rezeptoren bei der Entstehung von tumorinduziertem Schmerz untersucht werden. Im Unterschied zu neuropathischen Schmerzmodellen konnte gezeigt werden, dass beide TNF-Rezeptoren ausgeschaltet werden m{\"u}ssen, um eine signifikante Schmerzreduktion zu erzielen. Die systemische Behandlung mit dem TNF-neutralisierenden Fusionsprotein Etanercept konnte die im genetischen Modell gezeigte Reduktion der mechanischen Allodynie teilweise, aber nicht vollst{\"a}ndig reproduzieren. Eine Hemmung der Mikrogliaaktivierung mittels Minocyclin erbrachte im Tumor-schmerzmodell keinen Effekt auf das Schmerzverhalten der Tiere. Die histologische Analyse der tumoraffizierten Knochen zeigte eine signifikante Zunahme der Osteoklastenaktivit{\"a}t in tumortragenden Tieren. Die Behandlung mit Minocyclin war ohne erkennbaren Effekt auf die Differenzierung und die Aktivit{\"a}t der Osteoklasten. Es ergaben sich jedoch Hinweise, dass TNF-α einen hemmenden Einfluss auf die Osteoklastenaktivit{\"a}t im Knochentumormodell hat, da sowohl in den TNFR-KO-Tieren als auch unter Gabe von Etanercept eine Steigerung der Osteoklastenaktivit{\"a}t nachgewiesen werden konnte. Die Ergebnisse dieser Arbeit zeigen, dass TNF-α eine wichtige Rolle, sowohl in der Entstehung, als auch in der Aufrechterhaltung von tumorinduziertem Schmerz spielt. Hier liegt der Ansatzpunkt f{\"u}r weitere Studien mit dem Ziel, eine spezifische Pharmakotherapie zu entwickeln mit wirksamer TNF-α Blockade auch bei Patienten mit Tumorschmerzen. Nach den Erkenntnissen dieser Arbeit mit Etanercept sollte ein spezielles Augenmerk auf die ZNS-G{\"a}ngigkeit dieser Substanzen gelegt werden und die Gefahr der M{\"o}glichkeit eines vermehrten Tumorwachstum bedacht werden.}, subject = {Neuralgie}, language = {de} } @phdthesis{Gadeholt2012, author = {Gadeholt, Ottar}, title = {K{\"o}rperachsenorientierungsfehler - ein mit kognitiver Beeintr{\"a}chtigung assoziiertes neues klinisches Zeichen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-71952}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2012}, abstract = {Diese Studie zeigt, dass eine St{\"o}rung der K{\"o}rperachsenorientierung, manifestiert dadurch, dass beim Hinlegen die K{\"o}rperachse des Patienten von der L{\"a}ngsachse des Bettes abweicht, pr{\"a}diktiv f{\"u}r eine kognitive Beeintr{\"a}chtigung ist.}, subject = {K{\"o}rperachse}, language = {de} } @article{HagemannAnackerErnestusetal.2012, author = {Hagemann, Carsten and Anacker, Jelena and Ernestus, Ralf-Ingo and Vince, Giles H.}, title = {A complete compilation of matrix metalloproteinase expression in human malignant gliomas}, series = {World Journal of Clinical Oncology}, volume = {3}, journal = {World Journal of Clinical Oncology}, number = {5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-123982}, pages = {67-79}, year = {2012}, abstract = {Glioblastomas are characterized by an aggressive local growth pattern, a marked degree of invasiveness and poor prognosis. Tumor invasiveness is facilitated by the increased activity of proteolytic enzymes which are involved in destruction of the extracellular matrix of the surrounding healthy brain tissue. Elevated levels of matrix metalloproteinases (MMPs) were found in glioblastoma (GBM) cell-lines, as well as in GBM biopsies as compared with low-grade astrocytoma (LGA) and normal brain samples, indicating a role in malignant progression. A careful review of the available literature revealed that both the expression and role of several of the 23 human MMP proteins is controversely discussed and for some there are no data available at all. We therefore screened a panel of 15 LGA and 15 GBM biopsy samples for those MMPs for which there is either no, very limited or even contradictory data available. Hence, this is the first complete compilation of the expression pattern of all 23 human MMPs in astrocytic tumors. This study will support a better understanding of the specific expression patterns and interaction of proteolytic enzymes in malignant human glioma and may provide additional starting points for targeted patient therapy.}, language = {en} } @article{RadermacherWinglerKleikersetal.2012, author = {Radermacher, Kim A. and Wingler, Kirstin and Kleikers, Pamela and Altenh{\"o}fer, Sebastian and Hermans, Johannes J. R. and Kleinschnitz, Christoph and Schmidt, Harald H. H. W.}, title = {The 1027th target candidate in stroke: Will NADPH oxidase hold up?}, series = {Experimental and Translational Stroke Medicine}, volume = {4}, journal = {Experimental and Translational Stroke Medicine}, number = {11}, doi = {10.1186/2040-7378-4-11}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-124197}, year = {2012}, abstract = {As recently reviewed, 1026 neuroprotective drug candidates in stroke research have all failed on their road towards validation and clinical translation, reasons being quality issues in preclinical research and publication bias. Quality control guidelines for preclinical stroke studies have now been established. However, sufficient understanding of the underlying mechanisms of neuronal death after stroke that could be possibly translated into new therapies is lacking. One exception is the hypothesis that cellular death is mediated by oxidative stress. Oxidative stress is defined as an excess of reactive oxygen species (ROS) derived from different possible enzymatic sources. Among these, NADPH oxidases (NOX1-5) stand out as they represent the only known enzyme family that has no other function than to produce ROS. Based on data from different NOX knockout mouse models in ischemic stroke, the most relevant isoform appears to be NOX4. Here we discuss the state-of-the-art of this target with respect to stroke and open questions that need to be addressed on the path towards clinical translation.}, language = {en} } @article{AlbertWeissenbergerStetterMeuthetal.2012, author = {Albert-Weissenberger, Christiane and Stetter, Christian and Meuth, Sven G. and G{\"o}bel, Kerstin and Bader, Michael and Sir{\´e}n, Anna-Leena and Kleinschnitz, Christoph}, title = {Blocking of Bradykinin Receptor B1 Protects from Focal Closed Head Injury in Mice by Reducing Axonal Damage and Astroglia Activation}, series = {Journal of Cerebral Blood Flow and Metabolism}, volume = {32}, journal = {Journal of Cerebral Blood Flow and Metabolism}, number = {9}, doi = {10.1038/jcbfm.2012.62}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125903}, pages = {1747-1756}, year = {2012}, abstract = {The two bradykinin receptors B1R and B2R are central components of the kallikrein-kinin system with different expression kinetics and binding characteristics. Activation of these receptors by kinins triggers inflammatory responses in the target organ and in most situations enhances tissue damage. We could recently show that blocking of B1R, but not B2R, protects from cortical cryolesion by reducing inflammation and edema formation. In the present study, we investigated the role of B1R and B2R in a closed head model of focal traumatic brain injury (TBI; weight drop). Increased expression of B1R in the injured hemispheres of wild-type mice was restricted to the later stages after brain trauma, i.e. day 7 (P<0.05), whereas no significant induction could be observed for the B2R (P>0.05). Mice lacking the B1R, but not the B2R, showed less functional deficits on day 3 (P<0.001) and day 7 (P<0.001) compared with controls. Pharmacological blocking of B1R in wild-type mice had similar effects. Reduced axonal injury and astroglia activation could be identified as underlying mechanisms, while inhibition of B1R had only little influence on the local inflammatory response in this model. Inhibition of B1R may become a novel strategy to counteract trauma-induced neurodegeneration.}, language = {en} } @article{MichalskiHeindlKaczaetal.2012, author = {Michalski, D. and Heindl, M. and Kacza, J. and Laignel, F. and K{\"u}ppers-Tiedt, L. and Schneider, D. and Grosche, J. and Boltze, J. and L{\"o}hr, M. and Hobohm, C. and H{\"a}rtig, W.}, title = {Spatio-temporal course of macrophage-like cell accumulation after experimental embolic stroke depending on treatment with tissue plasminogen activator and its combination with hyperbaric oxygenation}, series = {European Journal of Histochemistry}, volume = {56}, journal = {European Journal of Histochemistry}, number = {2}, doi = {10.4081/ejh.2012.e14}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133136}, pages = {78 -- 89}, year = {2012}, abstract = {Inflammation following ischaemic stroke attracts high priority in current research, particularly using human-like models and long-term observation periods considering translational aspects. The present study aimed on the spatio-temporal course of macrophage-like cell accumulation after experimental thromboembolic stroke and addressed microglial and astroglial reactions in the ischaemic border zone. Further, effects of tissue plasminogen activator (tPA) as currently best treatment for stroke and the potentially neuroprotective co-administration of hyperbaric oxygen (HBO) were investigated. Rats underwent middle cerebral artery occlusion and were assigned to control, tPA or tPA+HBO. Twenty-four hours, 7, 14 and 28 days were determined as observation time points. The accumulation of macrophage-like cells was semiquantitatively assessed by CD68 staining in the ischaemic area and ischaemic border zone, and linked to the clinical course. CD11b, ionized calcium binding adaptor molecule 1 (Iba), glial fibrillary acidic protein (GFAP) and Neuronal Nuclei (NeuN) were applied to reveal delayed glial and neuronal alterations. In all groups, the accumulation of macrophage-like cells increased distinctly from 24 hours to 7 days post ischaemia. tPA+HBO tended to decrease macrophage-like cell accumulation at day 14 and 28. Overall, a trend towards an association of increased accumulation and pronounced reduction of the neurological deficit was found. Concerning delayed inflammatory reactions, an activation of microglia and astrocytes with co-occurring neuronal loss was observed on day 28. Thereby, astrogliosis was found circularly in contrast to microglial activation directly in the ischaemic area. This study supports previous data on long-lasting inflammatory processes following experimental stroke, and additionally provides region-specific details on glial reactions. The tendency towards a decreasing macrophage-like cell accumulation after tPA+HBO needs to be discussed critically since neuroprotective properties were recently ascribed to long-term inflammatory processes.}, language = {en} } @article{AhmadWolberEckardtetal.2012, author = {Ahmad, Ruhel and Wolber, Wanja and Eckardt, Sigrid and Koch, Philipp and Schmitt, Jessica and Semechkin, Ruslan and Geis, Christian and Heckmann, Manfred and Br{\"u}stle, Oliver and McLaughlin, John K. and Sir{\´e}n, Anna-Leena and M{\"u}ller, Albrecht M.}, title = {Functional Neuronal Cells Generated by Human Parthenogenetic Stem Cells}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {8}, doi = {10.1371/journal.pone.0042800}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130268}, pages = {e42800}, year = {2012}, abstract = {Parent of origin imprints on the genome have been implicated in the regulation of neural cell type differentiation. The ability of human parthenogenetic (PG) embryonic stem cells (hpESCs) to undergo neural lineage and cell type-specific differentiation is undefined. We determined the potential of hpESCs to differentiate into various neural subtypes. Concurrently, we examined DNA methylation and expression status of imprinted genes. Under culture conditions promoting neural differentiation, hpESC-derived neural stem cells (hpNSCs) gave rise to glia and neuron-like cells that expressed subtype-specific markers and generated action potentials. Analysis of imprinting in hpESCs and in hpNSCs revealed that maternal-specific gene expression patterns and imprinting marks were generally maintained in PG cells upon differentiation. Our results demonstrate that despite the lack of a paternal genome, hpESCs generate proliferating NSCs that are capable of differentiation into physiologically functional neuron-like cells and maintain allele-specific expression of imprinted genes. Thus, hpESCs can serve as a model to study the role of maternal and paternal genomes in neural development and to better understand imprinting-associated brain diseases.}, language = {en} } @phdthesis{Kindgen2012, author = {Kindgen, Andreas}, title = {Intraoperatives Monitoring mittels Elektrocochleographie (ECoG) und fr{\"u}her akustisch evozierter Potentiale (FAEP) zur {\"U}berwachung und Erhaltung der H{\"o}rfunktion in der kombinierten (neuro-/otochirurgischen) Behandlung intra-/extrameataler Akustikusneurinome}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-79625}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2012}, abstract = {Hintergrund: Obwohl als Standardverfahren bei der intraoperativen {\"U}berwachung bei der Akustikusneurinom (AN)-Chirurgie etabliert, handelt es sich bei der Ableitung akustisch evozierter Potentiale (AEP) um eine „Far-Field"-Technik mit einigen Einschr{\"a}nkungen. Diese Arbeit soll die Elektrocochleographie (ECoG) als Zusatzverfahren f{\"u}r den H{\"o}rerhalt {\"u}berpr{\"u}fen. Material und Methoden: 84 Patienten mit einseitigem intra-/extrameatalem AN (extrameataler Durchmesser 5-55mm) mit noch vorhandener H{\"o}rfunktion wurden unter Verwendung eines kombinierten neuro-/otochirurgischen suboccipitalen Zugangs operiert. Nach Einbringung einer Nadelelektrode auf das Promontorium unter otoskopischer Kontrolle wurden ECoG und AEP simultan abgeleitet. Ergebnisse: Bei 43 von 84 Patienten wurde ein H{\"o}rerhalt erzielt, wobei davon 40 sowohl AEP als auch ECoG aufwiesen. Alle 24 Patienten mit Verlust beider Modalit{\"a}ten wurden taub. H{\"o}rerhalt wurde bei 4 von 12 Patienten mit erhaltenem ECoG, aber Verlust des AEP (Wellen III-V) nachgewiesen, im umgekehrten Fall kam es zu postoperativer Taubheit in zwei F{\"a}llen. Trotz signifikanter Korrelation der AEP- und ECoG-Amplituden mit pr{\"a}- und postoperativem H{\"o}ren, erwiesen sich die Latenzen von Summations- und Aktionspotential als verl{\"a}ßlichere Indikatoren f{\"u}r H{\"o}rerhalt als beim AEP. Der Vorhersagewert erloschener AEP-Amplituden {\"u}bertraf den der ECoG-Parameter. Nur bei Tumoren {\"u}ber 2cm war die Gr{\"o}ße signifikant f{\"u}r den H{\"o}rerhalt. Außer postoperativer Otoliquorrhoe (3 Patienten) und einer lokalen Blutung im {\"a}ußeren Geh{\"o}rgang (1 Patient) wurden keine Nebenwirkungen beobachtet. Schlußfolgerung: Die ECoG-Ableitung erweist sich in Kombination mit AEPs als n{\"u}tzliches Zusatzverfahren zum H{\"o}rerhalt in der AN-Chirurgie. Besonders hilfreich ist es bei Verwendung der Bipolar-Pinzette sowie beim Bohren, da keine Mittelung notwendig ist. Spezielle Anwendungsm{\"o}glichkeiten sind kleine Tumoren mit funktioneller H{\"o}rfunktion und/oder einem großen intrameatalen Anteil sowie F{\"a}lle mit verlorenem oder gef{\"a}hrdetem kontralateralen H{\"o}ren (z. B. bilaterale AN), wenn sogar der Erhalt von nicht-funktionellem H{\"o}ren w{\"u}nschenswert ist.}, subject = {Elektrocochleographie}, language = {de} } @article{Westermaier2013, author = {Westermaier, Thomas}, title = {Neuroprotective Treatment Strategies for Delayed Cerebral Ischemia after Subarachnoid Hemorrhage - Review of Literature and Future Prospects}, doi = {10.4172/2155-9562.1000183}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-112631}, year = {2013}, abstract = {This article reviews experimental and clinical data on the use of various neuroprotective agents and therapeutic measures after aneurysmal subarachnoid hemorrhage (SAH). While calcium antagonists have been used in the past and are still part of the standard treatment regimen in most departments involved in the treatment of SAH, other classes of drugs and various other methods have been tested for their potential to inhibit delayed ischemia after SAH. This article reviews the literature about clinical studies about the efficacy of various neuroprotective agents and methods including statins, steroids and Endothelin-antagonists and other - alternative - methods like cisternal lavage, intrathecal drug delivery and hypercapnia, offering future perspectives for the treatment of this hazardous disease.}, language = {en} } @article{LinsenmannMonoranuKessleretal.2013, author = {Linsenmann, Thomas and Monoranu, Camelia M. and Kessler, Almuth F. and Ernestus, Ralf I. and Westermaier, Thomas}, title = {Bone chips, fibrin glue, and osteogeneration following lateral suboccipital craniectomy: a case report}, series = {BMC Research Notes}, journal = {BMC Research Notes}, doi = {10.1186/1756-0500-6-523}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97346}, year = {2013}, abstract = {Background Suboccipital craniectomy is a conventional approach for exploring cerebellopontine angle lesions. A variety of techniques have been successfully employed to reconstruct a craniectomy. This is the first report about the histological findings after performing a cranioplasty by using a mixture of autologous bone chips and human allogenic fibrin glue. Case presentation A 53-year-old German woman underwent left lateral suboccipital retrosigmoidal craniectomy for treatment of trigeminal neuralgia in 2008. Cranioplasty was perfomed by using a mixture of autologous bone chips and human allogenic fibrin glue. Due to recurrent neuralgia, a second left lateral suboccipital craniectomy was performed in 2012. The intraoperative findings revealed a complete ossification of the former craniotomy including widely mature trabecular bone tissue in the histological examination. Conclusion A mixture of autologous bone chips and human allogenic fibrin glue seems to provide sufficient bone-regeneration revealed by histological and neuroradiological examinations.}, language = {en} } @article{WestermaierStetterKunzeetal.2013, author = {Westermaier, Thomas and Stetter, Christian and Kunze, Ekkehard and Willner, Nadine and Raslan, Furat and Vince, Giles H. and Ernestus, Ralf-Ingo}, title = {Magnesium treatment for neuroprotection in ischemic diseases of the brain}, series = {Experimental and Translational Stroke Medicine}, journal = {Experimental and Translational Stroke Medicine}, doi = {10.1186/2040-7378-5-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96729}, year = {2013}, abstract = {This article reviews experimental and clinical data on the use of magnesium as a neuroprotective agent in various conditions of cerebral ischemia. Whereas magnesium has shown neuroprotective properties in animal models of global and focal cerebral ischemia, this effect could not be reproduced in a large human stroke trial. These conflicting results may be explained by the timing of treatment. While treatment can be started before or early after ischemia in experimental studies, there is an inevitable delay of treatment in human stroke. Magnesium administration to women at risk for preterm birth has been investigated in several randomized controlled trials and was found to reduce the risk of neurological deficits for the premature infant. Postnatal administration of magnesium to babies after perinatal asphyxia has been studied in a number of controlled clinical trials. The results are promising but the trials have, so far, been underpowered. In aneurysmal subarachnoid hemorrhage (SAH), cerebral ischemia arises with the onset of delayed cerebral vasospasm several days after aneurysm rupture. Similar to perinatal asphyxia in impending preterm delivery, treatment can be started prior to ischemia. The results of clinical trials are conflicting. Several clinical trials did not show an additive effect of magnesium with nimodipine, another calcium antagonist which is routinely administered to SAH patients in many centers. Other trials found a protective effect after magnesium therapy. Thus, it may still be a promising substance in the treatment of secondary cerebral ischemia after aneurysmal SAH. Future prospects of magnesium therapy are discussed.}, language = {en} } @article{LoehrMolcanyiPoggenborgetal.2013, author = {L{\"o}hr, Mario and Molcanyi, Marek and Poggenborg, J{\"o}rg and Spuentrup, Elmar and Runge, Matthias and R{\"o}hn, Gabriele and H{\"a}rtig, Wolfgang and Hescheler, J{\"u}rgen and Hampl, J{\"u}rgen A.}, title = {Intracerebral Administration of Heat-Inactivated Staphylococcus Epidermidis Enhances Oncolysis and Prolongs Survival in a 9L Orthotopic Gliosarcoma Model}, series = {Cellular Physiology and Biochemistry}, journal = {Cellular Physiology and Biochemistry}, doi = {10.1159/000350081}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96754}, year = {2013}, abstract = {Background/Aims: The association between postoperative infection and prolonged survival in high-grade glioma is still a matter of debate. Previously we demonstrated that the intracerebral (i.c.) injection of heat-inactivated staphylococcal epitopes (HISE) resulted in a well-defined infux of immunocompetent cells across the blood-brain barrier. The present study investigated the potential antitumoral effect of HISE-immunostimulation in an experimental glioma model. Methods: Wistar rats were intracerebrally implanted with 9L gliosarcoma cells (n=6), 9L cells mixed with HISE (n=12), or phosphate buffered saline (n=4). Tumor growth was measured by serial magnetic resonance imaging (MRI). After death due to the tumor burden, the brains were histopathologically assessed for inflammation and oncolysis. A toxicity assay was performed to quantify potential impairment of HISE on tumor cell growth in vitro. Results: Animals treated by HISE showed a significant increase in average survival and even complete regression of an already established mass in one case. Na{\"i}ve 9L gliosarcomas failed to recruit significant numbers of systemic immune cells. In contrast, concomitant intracerebral HISE inoculation lead to a oncolysis and a distinct peri- and intratumoral infiltration of macrophages, CD8 and CD4 co-expressing T-lymphocytes in two thirds of the tumor-bearing animals. The toxicity screening showed HISE-mediated oncolysis to be ineffective ex vivo. Conclusion: This study describes a novel approach for combatting malignant glioma using inactivated staphylococci as potent immunomodulators. Our results provide an outline for investigating the strategic potential of bacteria as emerging future therapeutics.}, language = {en} } @article{SirenStetterHirschbergetal.2013, author = {Sir{\´e}n, Anna-Leena and Stetter, Christian and Hirschberg, Markus and Nieswandt, Bernhard and Ernestus, Ralf-Ingo and Heckmann, Manfred}, title = {An experimental protocol for in vivo imaging of neuronal structural plasticity with 2-photon microscopy in mice}, series = {Experimental \& Translational Stroke Medicine}, journal = {Experimental \& Translational Stroke Medicine}, doi = {10.1186/2040-7378-5-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96908}, year = {2013}, abstract = {Introduction Structural plasticity with synapse formation and elimination is a key component of memory capacity and may be critical for functional recovery after brain injury. Here we describe in detail two surgical techniques to create a cranial window in mice and show crucial points in the procedure for long-term repeated in vivo imaging of synaptic structural plasticity in the mouse neocortex. Methods Transgenic Thy1-YFP(H) mice expressing yellow-fluorescent protein (YFP) in layer-5 pyramidal neurons were prepared under anesthesia for in vivo imaging of dendritic spines in the parietal cortex either with an open-skull glass or thinned skull window. After a recovery period of 14 days, imaging sessions of 45-60 min in duration were started under fluothane anesthesia. To reduce respiration-induced movement artifacts, the skull was glued to a stainless steel plate fixed to metal base. The animals were set under a two-photon microscope with multifocal scanhead splitter (TriMScope, LaVision BioTec) and the Ti-sapphire laser was tuned to the optimal excitation wavelength for YFP (890 nm). Images were acquired by using a 20×, 0.95 NA, water-immersion objective (Olympus) in imaging depth of 100-200 μm from the pial surface. Two-dimensional projections of three-dimensional image stacks containing dendritic segments of interest were saved for further analysis. At the end of the last imaging session, the mice were decapitated and the brains removed for histological analysis. Results Repeated in vivo imaging of dendritic spines of the layer-5 pyramidal neurons was successful using both open-skull glass and thinned skull windows. Both window techniques were associated with low phototoxicity after repeated sessions of imaging. Conclusions Repeated imaging of dendritic spines in vivo allows monitoring of long-term structural dynamics of synapses. When carefully controlled for influence of repeated anesthesia and phototoxicity, the method will be suitable to study changes in synaptic structural plasticity after brain injury.}, language = {en} } @phdthesis{Wesche2013, author = {Wesche, Manuel}, title = {Entwicklung einer Methode zur Herstellung von kommunizierenden Neuronen-Netzwerken auf Multielektroden Arrays}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-83689}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Ziel der Arbeit war es, dichte Neuronenkulturen in kleinere Untereinheiten zu unterteilen, welche durch ihre Neuriten miteinander in Kontakt standen. Zu diesem Zweck wurden auf MEAs zellbindende Kreisareale mittels Mikrostempeltechnik auf die zellabweisende Schicht aus Polyethylenglykol {\"u}bertragen. Dudurch wurde gew{\"a}hrleistet, dass scharf abgegrenzte Neuronenareale f{\"u}r mehrere Wochen auf dem MEA wuchsen und nach Ausbildung der neuritischen Verbindungen untereinander, die elektrische Aktivit{\"a}t zwischen den Kreiskammern gemessen werden k{\"o}nnte. Das sollte Auskunft {\"u}ber Informationsausbreitung in Neuralnetzen geben und die Theorien {\"u}ber Synchronit{\"a}t und Synfirechains pr{\"u}fbar machen.}, subject = {MEA}, language = {de} } @article{AlbertWeissenbergerMenclSchuhmannetal.2014, author = {Albert-Weissenberger, Christiane and Mencl, Stine and Schuhmann, Michael K. and Salur, Irmak and G{\"o}b, Eva and Langhauser, Friederike and Hopp, Sarah and Hennig, Nelli and Meuth, Sven G. and Nolte, Marc W. and Sir{\´e}n, Anna-Leena and Kleinschnitz, Christoph}, title = {C1-Inhibitor protects from focal brain trauma in a cortical cryolesion mice model by reducing thrombo-inflammation}, series = {Frontiers in Cellular Neuroscience}, volume = {8}, journal = {Frontiers in Cellular Neuroscience}, issn = {1662-5102}, doi = {10.3389/fncel.2014.00269}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119263}, pages = {269}, year = {2014}, abstract = {Traumatic brain injury (TBI) induces a strong inflammatory response which includes blood-brain barrier damage, edema formation and infiltration of different immune cell subsets. More recently, microvascular thrombosis has been identified as another pathophysiological feature of TBI. The contact-kinin system represents an interface between inflammatory and thrombotic circuits and is activated in different neurological diseases. C1-Inhibitor counteracts activation of the contact-kinin system at multiple levels. We investigated the therapeutic potential of C1-Inhibitor in a model of TBI. Male and female C57BL/6 mice were subjected to cortical cryolesion and treated with C1-Inhibitor after 1 h. Lesion volumes were assessed between day 1 and day 5 and blood-brain barrier damage, thrombus formation as well as the local inflammatory response were determined post TBI. Treatment of male mice with 15.0 IU C1-Inhibitor, but not 7.5 IU, 1 h after cryolesion reduced lesion volumes by ~75\% on day 1. This protective effect was preserved in female mice and at later stages of trauma. Mechanistically, C1-Inhibitor stabilized the blood-brain barrier and decreased the invasion of immune cells into the brain parenchyma. Moreover, C1-Inhibitor had strong antithrombotic effects. C1-Inhibitor represents a multifaceted anti-inflammatory and antithrombotic compound that prevents traumatic neurodegeneration in clinically meaningful settings.}, language = {en} } @article{NiklassStoyanovGarzetal.2014, author = {Niklass, Solveig and Stoyanov, Stoyan and Garz, Cornelia and Bueche, Celine Z. and Mencl, Stine and Reymann, Klaus and Heinze, Hans-Jochen and Carare, Roxana O. and Kleinschnitz, Christoph and Schreiber, Stefanie}, title = {Intravital imaging in spontaneously hypertensive stroke-prone rats-a pilot study}, series = {Experimental \& Translational Stroke Medicine}, volume = {6}, journal = {Experimental \& Translational Stroke Medicine}, doi = {10.1186/2040-7378-6-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-121353}, pages = {1}, year = {2014}, abstract = {Background There is growing evidence that endothelial failure and subsequent blood brain barrier (BBB) breakdown initiate cerebral small vessel disease (CSVD) pathology. In spontaneously hypertensive stroke-prone rats (SHRSP) endothelial damage is indicated by intraluminal accumulations of erythrocytes (erythrocyte thrombi) that are not observed with current magnetic resonance imaging techniques. Two-photon microscopy (2 PM) offers the potential for real-time direct detection of the small vasculature. Thus, within this pilot study we investigated the sensitivity of 2 PM to detect erythrocyte thrombi expressing initiating CSVD phenomena in vivo. Methods Eight SHRSP and 13 Wistar controls were used for in vivo imaging and subsequent histology with haematoxylin-eosin (HE). For 2 PM, cerebral blood vessels were labeled by fluorescent Dextran (70 kDa) applied intraorbitally. The correlation between vascular erythrocyte thrombi observed by 2 PM and HE-staining was assessed. Artificial surgical damage and parenchymal Dextran distribution were analyzed postmortem. Results Dextran was distributed within the small vessel walls and co-localized with IgG. Artificial surgical damage was comparable between SHRSP and Wistar controls and mainly affected the small vasculature. In fewer than 20\% of animals there was correlation between erythrocyte thrombi as observed with 2 PM and histologically with HE. Conclusions Contrary to our initial expectations, there was little agreement between intravital 2 PM imaging and histology for the detection of erythrocyte thrombi. Two-photon microscopy is a valuable technique that complements but does not replace the value of conventional histology.}, language = {en} } @article{AlbertWeissenbergerMenclHoppetal.2014, author = {Albert-Weissenberger, Christiane and Mencl, Stine and Hopp, Sarah and Kleinschnitz, Christoph and Siren, Anna-Leena}, title = {Role of the kallikrein-kinin system in traumatic brain injury}, series = {Frontiers in Cellular Neuroscience}, volume = {8}, journal = {Frontiers in Cellular Neuroscience}, issn = {1662-5102}, doi = {10.3389/fncel.2014.00345}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-118226}, pages = {345}, year = {2014}, abstract = {Traumatic brain injury (TBI) is a major cause of mortality and morbidity worldwide. Despite improvements in acute intensive care, there are currently no specific therapies to ameliorate the effects of TBI. Successful therapeutic strategies for TBI should target multiple pathophysiologic mechanisms that occur at different stages of brain injury. The kallikrein-kinin system is a promising therapeutic target for TBI as it mediates key pathologic events of traumatic brain damage, such as edema formation, inflammation, and thrombosis. Selective and specific kinin receptor antagonists and inhibitors of plasma kallikrein and coagulation factor XII have been developed, and have already shown therapeutic efficacy in animal models of stroke and TBI. However, conflicting preclinical evaluation, as well as limited and inconclusive data from clinical trials in TBI, suggests that caution should be taken before transferring observations made in animals to humans. This review summarizes current evidence on the pathologic significance of the kallikrein-kinin system during TBI in animal models and, where available, the experimental findings are compared with human data.}, language = {en} }