TY - JOUR A1 - Jaiswal, Neelam A1 - Lambrecht, Günter A1 - Mutschler, Ernst A1 - Tacke, Reinhold A1 - Malik, Kafait U. T1 - Pharmacological characterization of the vascular muscarinic receptors mediating relaxation and contraction in rabbit aorta JF - Journal of Pharmacology and Experimental Therapeutics N2 - Studies were performed in the rabbit aortic rings, precontracted with norepinephrine, to determine the subtype(s) of muscarinic receptors involved in endothelium-dependent relaxation and contraction in the absence of endothelium elicited by cholinergic stimuli. Acetylcholine (ACh) and arecaidine propargyl ester (APE), a M2 and M3 agonist, produced a dose-dependent relaxation and contraction in endothelium-intact and endothelium-denuded rabbit aortic rings, respectively. Both of these responses were blocked by the muscarinic receptor antagonist atropine. M1 selective agonist McN-A-343 [4-[N-(3-chlorophenyl)carbamoyloxy]-2-butinyltrimethylammonium+ ++ chloride] did not produce any effect on the tone of precontracted aortic rings. ACh- and APE-induced relaxation in aortic rings with intact endothelium was selectively blocked by M3 receptor antagonists hexahydrosila-difenidol and p-fluoro-hexahydro-sila-difenidol (pA2 of 7.84 and 7.18) but not by M1 antagonist pirenzepine or M2 receptor antagonists AF-DX 116 [11-(2-[(diethylamino)methyl]- 1-piperidinyl]acetyl)-5, 11-dihydro-6H-pyrido-[2,3-b][1,4]-benzo-diazepin-6-one] and methoctramine. ACh- and APE-induced contraction was inhibited by M2 receptor antagonists AF-DX 116 and methoctramine (pA2 of 7.11 and 6.71) but not by pirenzepine, hexahydro-sila-difenidol or p-fluoro-hexahydro-sila-difenidol. ACh- and APE-induced relaxation or contraction were not altered by nicotinic receptor antagonist hexamethonium or cyclooxygenase inhibitor indomethacin. These data suggest that relaxation elicited by cholinergic stimulin in endothelium-intact aortic rings is mediated via release of endothelium-derived relaxing factor consequent to activation of M3 receptors located on endothelial cells, whereas the contraction in aortic rings denuded of their endothelium is mediated via stimulation of M2 receptors located on smooth muscle cells. KW - (4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium chloride/pharmacology KW - acetylcholine KW - animals KW - antihypertensive agents / pharmacology KW - aorta, abdominal / drug effects KW - aorta, abdominal / physiology KW - aorta, abdominal / ultrastructure KW - arecoline/analogs & derivatives KW - arecoline KW - atropine KW - diamines KW - endothelium, vascular / drug effects KW - endothelium, vascular / physiology KW - hexamethonium KW - hexamethonium compounds KW - indomethacin KW - male KW - muscarinic antagonists KW - muscle contraction KW - muscle relaxation KW - norepinephrine KW - parasympatholytics KW - piperidines KW - pirenzepine KW - rabbits Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128358 VL - 258 IS - 3 ER - TY - JOUR A1 - Adam, Dieter A1 - Maueler, Winfried A1 - Schartl, Manfred T1 - Transcriptional activation of the melanoma inducing Xmrk oncogene in Xiphophorus N2 - The melanoma inducing locus of Xiphophorus encodes a tumorigenic version of a novel putative receptor tyrosine kinase (Xmrk). To elucidate the mechanism of oncogenic activation of Xmrk, we compared the structure and expression of two oncogenic loci with the corresponding proto-oncogene. Only minor structural alterations were found to be specific for the oncogenic Xmrk genes. Marked overexpression of the oncogene transcripts in melanoma, which are approximately 1 kb shorter than the proto-oncogene transcript, correlates with the malignancy of the tumors. The tumor transcripts are derived from an alternative transcription start site that is used only in the oncogenic loci. Thus, oncogenic activation of the melanoma inducing Xmrk gene appears primarily to be due to novel transcriptional control and overexpression. KW - Schwertkärpfling KW - Onkogen KW - Melanom Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-87584 ER - TY - JOUR A1 - Hannig, Gerhard A1 - Ottilie, Sabine A1 - Schartl, Manfred T1 - Conservation of structure and expression of the c-yes and fyn genes in lower vertebrates N2 - The src-gene family in mammals and birds consists of 9 closely related protein tyrosine kinases. We have cloned the c-yes and fyn bomologues of the src-family from the teleost fish Xiphophorus helleri. Both genes show a high degree of sequence conservation and exhibit all structural motifs diagnostic for functional src-like protein tyrosine kinases. Sequence comparisons revealed three domains (exon 2, exons 3--6, exons 7-12) which evolve at different rates. Both genes exhibit an identical expression pattern, with preferential expression in neural tissues. No transcripts of c-yes were found in liver wbich is contrary to the situation in higher vertebrales. In malignant melanoma, elevated Ieveis of c-yes andfyn were detected indicating a possible function during secondary steps of tumor progression for src-related tyrosine kinases. KW - Konservierung KW - Gen KW - Niedere Wirbeltiere Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86723 ER - TY - JOUR A1 - Näslund, Jan Carol A1 - Schneider, Wolfgang T1 - Longitudinal effects of verbal ability, memory capacity, and phonological awareness on reading performance N2 - This study addresses the longitudinal relationship among verbal ability, memory capacity, phonological awareness, and reading performance. Data from 92 German children were used to explore the exact relation among these variables. Indicators of verbal ability, memory capacity, and phonological awareness were assessed in kindergarten and again after the first grade. The interrelationships among these factors, and the subsequent influence they have on decoding speed and reading comprehension during the second grade were examined via structural equation modefing procedures. Overall, the results of the longitudinal analyses show that the relationship of memory capacity and phonological awareness remains stable over time, and that memory capacity predicts performance on phonological awareness tasks in both kindergarten and second grade. Phonological awareness proved to be a significant predictor of decoding speed, which in turn considerably influenced reading comprehension. KW - Lesefähigkeit KW - Sprachfertigkeit KW - Gedächtnisleistung KW - Phonologische Bewusstheit Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86606 ER - TY - JOUR A1 - Schartl, Manfred A1 - Erbelding-Denk, Claudia A1 - Nanda, Indrajit A1 - Schmid, Michael A1 - Schröder, Johannes Horst A1 - Epplen, Jörg T. T1 - Mating success of subordinate males in a poeciliid fish species, Limia perugiae N2 - No abstract available. KW - Lebendgebärende Zahnkarpfen KW - Perugia-Kärpfling Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86349 ER - TY - JOUR A1 - Schroten, Horst A1 - Wolske, Anja A1 - Plogmann, Ricarda A1 - Hanisch, Franz-Georg A1 - Hacker, Jörg A1 - Uhlenbrück, Gerhard A1 - Wahn, Volker T1 - Binding of cloned S-fimbriated E. coli to human buccal epithelial cells-different inhibition of binding by neonatal saliva and adult saliva. N2 - Investigations were carried out on the adhesion of cloned S-fimbriated E. coli, labelled with fluoresceinisothiocyanate (FITC) to human buccal epithelial cells. Fluorescence microscopic analysis revealed binding of bacteria to 75-95% of epithelial cells. Inhibition experiments with fetuin, a 1-acid glycoprotein and N-acetyl neuraminic acid confirmed the specificity of bacterial binding to sialoglycoproteins. Further studies using saliva as an inhibitor resulted in a 4-5 times stronger binding inhibition by newborn saliva in comparison to adult saliva coinciding with a 4-5 times higher content of total N-acetyl neuraminic acid in samples of newborn saliva. In Western blot analysis sialoglycoprotein bands with a molecular weight >200 kD reacting with wheat germ agglutinin (WGA), were only identified in samples of newborn saliva. These bands are classified as mucins on account of molecular weight and staining. These data suggest that saliva mucins could represent a major defense mechanism against bacterial infections at a stage of ontogeny where the secretory IgAsystem is not yet developed. N2 - bestätigt werden. Wurde als Inhibitor Speichel eingesetzt, so ergab sich für den Speichel Neugeborener eine 4-Sfach stärkere Inhibition als für Erwachsenenspeichel Parallel dazu ergab die Untersuchung der Speichelproben für Neugeborene einen 4-Sfachen höheren. Die Adhäsion clonierter, Fluoresceinisothiocyanat (FITC)-markierter, S-Fimbrien tragender E. coli an menschliche Mundschleimhautzellen wurde untersucht. Die fluoreszenzmikroskopische Auswertung ergab, daß 75-95% der Schleimhautzellen Bakterien gebunden hatten. Die Spezifität der Bindung der Bakterien an Sialoglykoproteine konnte durch Inhibitionsexperimente mit Fetuin, saurem arGlykoprotein und N-acetyl-Neuraminsäure Gehalt an Gesamt-N-acetyl-Neuraminsäure. In Westerohlot Analysen konnten nur in Proben nativen Speichels Neugeborener mit Wheat Germ Agglutinin (WGA) reagierende Sialoglykoproteinbanden mit Molekülmassen > 200 kD identifiziert werden, die aufgrund ihres Molekulargewichtes und Färbeverhaltens der Klasse der Mucine zuzuordnen sind. Speichelmucine können einen wichtigen Abwehrmechanismus gegen Infektionen in einer Periode der kindlichen Entwicklung darstellen, in der das sekretorische IgA-System noch nicht voll entwickelt ist. KW - Escherichia coli KW - Speichel KW - Neugeborenes KW - Erwachsener KW - Adhäsion Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86291 ER - TY - JOUR A1 - Wilhelm, Gernot A1 - Zaccagnini, Carlo T1 - Excavations at Tell Karrana 3 (1985 and 1986) N2 - no Abstract available KW - Tell Karrana Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-85963 ER - TY - JOUR A1 - Wilhelm, Gernot T1 - A Hurrian Letter from Tell Brak N2 - No abstract available. KW - Tell Brak Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-85972 ER - TY - JOUR A1 - Lohse, Martin J. A1 - Klotz, Karl-Norbert A1 - Schwabe, Ulrich T1 - Mechanism of A2 adenosine receptor activation. I. Blockade of A2 adenosine receptors by photoaffinity labeling N2 - It has previously been shown that covalent incorporation of the photoreactive adenosine derivative (R)-2-azido-N6-p-hydroxyphenytisopropyladenosine [(R)-AHPIA] into the A, adenosine receptor of intact fat cells leads to a persistent activation of this receptor, resulting in a reduction of celular cAMP Ieveis [Mol. Pharmacol. 30:403-409 (1986)]. In contrast, covalent incorporation of (R)-AHPIA into human platelet membranes, which contain only stimulatory A2 adenosine receptors, reduces adenytate cyclase Stimulation via these receptors. This effect of (R)-AHPIA is specific for the A2 receptor and can be prevented by the adenosine receptor antagonist theophylline. Binding studies in-dicate that up to 90% of A2 receptors can be blocked by photoincorporation of (R)-AHPIA. However, the remaining 10-20% of A2 receptors are sufficient to mediate an adenylate cyclase Stimulation of up to SOOk of the control value. Similarly, the activation via these 10-20% of receptors occurs with a halflife that is only 2 times Ionger than that in control membranes. This indicates the presence of a receptor reserve, with respect to both the extent and the rate of adenytate cyclase Stimulation. These observations require a modification of the models of receptor-adenytate cyclase coupling, which is described in the accompanying paper [Mol. Pharmacol. 39:524-530 (1991)]. KW - Adenosinrezeptor Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86073 ER - TY - JOUR A1 - Gonzalez-Calero, G. A1 - Cubero, A. A1 - Klotz, Karl-Norbert T1 - Characterization and photoaffinity labeling of A1 adenosine receptors in coated visicles form bovine brain N2 - The antagonist (3 II ) DPCPX exhi bitcd a Kd of 0. 4 nM at coalcd vcsicles from bovine brain. Agonist compelition for ( 3 11) DPCPX bind in~ revcaled two affini ty slales for gonists. The pholoaffinity probe I25 I -AHPIA specifically labelled a band with a molecular weight of 35 Kd. KW - Pharmakologie Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86004 ER -