TY - JOUR A1 - Ulrichs, Karin A1 - Keller, R. A1 - Müller-Ruchholtz, W. T1 - Serological demonstration and manipulation of passenger cells (PC) in pancreas islet grafts N2 - No abstract available KW - Immunobiologie Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-72944 ER - TY - JOUR A1 - Simon, M. M. A1 - Nerz, G. A1 - Prester, M. A1 - Moll, Heidrun T1 - Immunoregulation by mouse T cell clones III. Cloned H-Y-specific cytotoxic T cells secrete a soluble mediator(s) that inhibits cytotoxic responses by acting on both Lyt-2\(^-\) and L3T4\(^-\)- lymphocytes N2 - In this study we report that cloned Thy-l +, L3T4-, Lyt-l-, Lyt-2+, H-Y-specific and H-2Db-restricted cytotoxic T ce11 lines (CTLL) when indueed by lectin or antigen secrete a soluble mediator(s) (SF) that inhibits proliferation and generation of cytotoxic lymphocytes (CTL) in mixed lymphocyte cultures (MLC). The biological activity was separable by gel filtration and appeared as a broad peak in the moleeular mass range between 10000 and 50000 kDa. It was found that the suppressive activity released by CTLL neither strictly correlates with their cytotoxic potential nor with their ability to produce immune interferon or Iymphotoxin. SF was shown to elicitits activity in an antigen-nonspeeific manner in that it suppressed the maturation of T lymphocytes responding to both, the appropriate H-Y antigen as weH as to unrelated H_2d alloantigens or to the hapten 2,4,6-trinitrophenyl (TNP). The effect of SF on CTL responses was most pronounced in early phases of primary or secondary MLC. When analyzed for its inhibitory activity on precursor ceHs in populations selected for either Lyt-2- or L3T4- lymphocytes, it was found that SF interfered with the maturation of both subsets. The inhibition of CTL responses elicited by SF could not be reversed by the addition of exogenous interleukin 2. The findtng that SF also inhi. bited the proliferation of some but not a11 antigen-dependent cloned T ceHs with helper or eytc'toxic potential provides evidence that the faetor also may regulate effector lymphl)cytes. In addition, the results support the assumption that SF exerts its effect direetly on the responder rather than the stimulator population, and demonstrate that the development of CTL from their preeursor eeHs is contro11ed at least in part by the eytotoxic effeetor cells themselves via a soluble factor(s) that interferes with distinct stages of T ce11 maturation. These findings again emphasize the expression of multiple functions by CTL and indieate their possible role du ring the course of an immune response by their capability to eliminate target cells and to secrete a soluble product(s) that mediates feedback contro!. KW - Infektionsbiologie Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31625 ER - TY - JOUR A1 - Schmähl, D. A1 - Frank, HK A1 - Lutz, WK A1 - Stransky, M. A1 - Ritzel, G. A1 - Beaufort, F. A1 - Vutuc, C. T1 - Ernährung und Krebs N2 - No abstract available KW - Medizin Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-55224 ER - TY - JOUR A1 - Sirén, Anna-Leena A1 - Svarström-Fraser, M. A1 - Paakkari, I. T1 - Central cardiovascular effects of the endoperoxide analogue U-46619 i.c.v. in rats N2 - 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. KW - Medizin Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-49064 ER - TY - JOUR A1 - Artyukova, E. V. A1 - Gorboulev, Valentin G. A1 - Rodionova, N. P. A1 - Krylov, A. V. A1 - Atabekov, J. G. T1 - Comparative study of structural peculiarities and translation of potexvirus RNAs N2 - Structural peculiarities of the S'-end segments of genomic RNA were studied in F potato virus (F-PV) and white clover mosaic virus (WCMV). The methods of affinity chromatography on oligo(dT) cellulose and oligonucleotide mapping revealed a prolonged (up to 210 nucleotides) polyadenyl sequence at the 3'-end of F-PV RNA. A polyadenyl sequence is missing at the 3'end of WCMV RNA. A study of the translation products of WCMV and F-PV RNAs in a oe11-free protein-synthesizing system derived from rabbit reticulocytes showed that polypeptides electrophoretically comigrating with a structural protein of either virus were synthesized alongside high-molecular-weight polypeptides (M\(_r\)\(\approx\) 180-150 kdaltons). Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46985 ER - TY - JOUR A1 - Ulrichs, Karin A1 - Müller-Ruchholtz, W. T1 - Further Analyses of Pancreas Islet Immunogenicity, a Major Barrier to Successful Islet Transplantation N2 - No abstract available KW - Chirurgie Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45563 ER - TY - JOUR A1 - Ulrichs, Karin A1 - Müller-Buchholtz, W. T1 - MHC class II antigen expression on the various cells of normal and activated isolated pancreatic islets N2 - It is the aim of this study to characterize and quantify the cells within isolated rat islets that express MHC class 11 antigens. A set of five monoelonal antibodies and two polyclonal antisera of defined specificlty were used in combination with a newly devised procedure for three·dimensional immunofluorescence evaluation of intact islets. It is shown that in addition to passen· ger cells, such as Iymphocytes, macro· phages, and dendrlticlike cells, vascular endothelial and endocrine cells are also capable of expressing class 11 antigens. This expression Is strongly influenced by in vitro culture. pregnancy, streptozotocin- induced diabetes, transplantation trauma, and alloantigenic stimuli. The pos· sible role of the above cells in antigen presentation related to islet transplantation is discussed. KW - pancreas Islets KW - beta cells KW - islet transplantation KW - la antigens Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-44722 ER - TY - JOUR A1 - Rubtsov, P. M. A1 - Chernov, V. G. A1 - Gorboulev, Valentin G. A1 - Parsadanyan, A. S. A1 - Sverdlova, P. S. A1 - Chupeeva, V. V. A1 - Golova, Yu. B. A1 - Batchikova, N. V. A1 - Zvirblis, G. S. A1 - Skryabin, K. G. A1 - Bayev, A. A. T1 - Genetic engineering of peptide hormones N2 - Peptide and polypeptide hormones represent an extensive group of biologically active compounds of important significance for medicine and agriculture. In recent years genetic engineering methods have been used to create strains of microorganisms synthesizing eukaryotic proteins, including hormones and their precursors. The first stage of such developments is the isolation of DNA coding the des~red product. We have accomplished the cloning of the cDNA of a number of polypeptide and peptide hormones of the pituitary of man and domestic animals. The model gene of human calcitonin has also been synthesized and cloned. The obtained genes are being used to develop methods for the microbiological synthesis of human and animal-hormones. Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46964 ER - TY - JOUR A1 - Lohse, M. J. A1 - Klotz, Karl-Norbert A1 - Jakobs, K. H. A1 - Schwabe, U. T1 - Barbiturates are selective antagonists at A\(_1\) adenosine receptors N2 - Barbiturates in pharmacologically relevant . concentrations inhibit binding of (R)-\(N^6\)-phenylisopropyl[\(^3\)H]adenosine ([\(^3\)H]PIA) to solubilized A\(_1\) adenosine receptors in a concentration-dependent, stereospecific, and competitive manner. K\(_i\) values are similar to those obtained for membrane-bound receptors and are 31 \(\mu\)M for ( ± )-5-(1 ,3-dimethyl)-5-ethylbarbituric acid [( ± )DMBB] and 89 \(\mu\)M for ( ± )-pentobarbital. Kinetic experiments demoostrate that barbiturates compete directly for the binding site of the receptor. The inhibition of rat striatal adenylate cyclase by unlabelled (R)-\(N^6\)-phenylisopropyladenosine [(R)-PIA] is antagonized by barbiturates in the same concentrations that inhibit radioligand binding. The Stimulation of adenylate cyclase via A\(_2\) adenosine receptors in membranes from NIE 115 neuroblastoma cells is antagonized only by 10-30 times higher concentrations of barbiturates. lt is concluded that barbiturates are selective antagonists at the A1 receptor subtype. In analogy to the excitatory effects of methylxanthines it is suggested that A\(_1\) adenosine receptor antagonism may convey excitatory properties to barbiturates. Key Words: Adenosine receptors-Barbiturates - Adenylate cyclase-Receptor solubilization-[3H]PIA binding-N1E 115 cells. Lohse M. J. et al. Barbiturates are selective antagonists at A1 adenosine receptors. KW - Toxikologie KW - adenosine receptors KW - barbiturates KW - adenylate cyclase KW - receptor solubilization KW - N1E 115 cells KW - [3H]PIA binding Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60187 ER - TY - JOUR A1 - Klotz, Karl-Norbert A1 - Cristalli, G. A1 - Grifantini, M. A1 - Vittori, S. A1 - Lohse, M. J. T1 - Photoaffinity labeling of A\(_1\) adenosine receptors JF - The journal of biological chemistry N2 - The ligand-binding subunit of the A\(_1\)-adenosine receptor has been identified by photoaffinity labeling. A photolabile derivative of R- \(N^6\)-phenylisopropyladenosine, R-2-azido-\(N^6\)-p-hydroxyphenylisopropyladenosine (R-AHPIA), has been synthesized as a covalent specific Iigand for A\(_1\)-adenosine receptors. In adenylate cyclase studies with membranes of rat fat cells and human platelets, R·AHPIA has adenosine receptor agonist activity with a more than 60-fold selectivity for the A\(_1\)-subtype. It competes for [\(^3\)H].\(N^6\)- phenylisopropyladenosine binding to Arreceptors of rat brain membranes with a Ki value of 1.6 nM. After UV irradiation, R-AHPIA binds irreversibly to the receptor, as indicated by a loss of [\(^3\)H)\(N^6\)-phenylisopropyladenosine binding afterextensive washing; the K; value for this photoinactivation is 1.3 nM. The p-hydroxyphenyl substituent of R-AHPIA can be directly radioiodinated to give a photoaffinity Iabel of high specific radioactivity (\(^{125}\)I-AHPIA). This compound has a KD value of about 1.5 nM as assessed from saturation and kinetic experiments. Adenosine analogues compete for \(^{125}\)I-AHPIA binding to rat brain membranes with an order of potency characteristic for A\(_1\)-adenosine receptors. Dissociation curves following UV irradiation at equilibrium demonstrate 30-40% irreversible specific binding. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicates that the probe is photoincorporated into a single peptide of M\(_r\) = 35,000. Labeling of this peptide can be blocked specifically and stereoselectively by adenosine receptor agonists and antagonists in a manner which is typical for the A\(_1\)-subtype. The results indicate that \(^{125}\)I-AHPIA identifies the ligand-binding subunit of the A\(_1\)-adenosine receptor, which is a peptide with M\(_r\) = 35,000. KW - Toxikologie Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60198 VL - 27 IS - 260 ER -