title: Arginine vasopressin and oxytocin increase intracellular calcium and cAMP in human glomerular epithelial cells in culture.
abstract: The signal transduction linkages of arginine vasopressin (AVP) and oxytocin receptors were investigated in human glomerular epithelial cells (GEC) in culture. AVP (ED50, 10(-7) mol/l) and oxytocin (ED50, 3 x 10(-8) mol/l) induced a rapid, transient and dose-dependent increase in [Ca2+]i as detected by fura-2 microfluorimetry. The baseline of [Ca2+]i in human GEC was 109 +/- 2.8 nmol/l (n = 60). The V1a receptor antagonist [d(CH2)5(1), Tyr(Me)2, Arg8]-vasopressin inhibited the AVP-(IC50, 5 x 10(-9) mol/l) and oxytocin-induced (IC50, 3 x 10(-8) mol/l) increase in [Ca2+]i in a dose-dependent manner. Both, AVP and oxytocin caused accumulation of cAMP. The AVP-stimulated cAMP increase was blocked by pretreatment of human GEC with the V1a receptor antagonist (10(-7) mol/l), whereas the oxytocin-induced cAMP accumulation remained uninfluenced. In conclusion the present results indicate that: (1) V1a receptor activation, AVP and oxytocin induce a transient elevation in [Ca2+]i in human GEC; (2) AVP and oxytocin cause cAMP accumulation; (3) the AVP-induced cAMP accumulation is inhibited by a V1a receptor antagonist, whereas (4) the oxytocin response showed no effect. In addition, a different receptor might be possible, at least in oxytocin-induced-cAMP accumulation.
authors.affiliation: Medizinische Universitätsklinik, Abteilung Innere Medizin IV, Freiburg, Deutschland.
authors.forename: M
authors.initials: M
authors.lastname: Späth
authors.forename: H
authors.initials: H
authors.lastname: Pavenstädt
authors.forename: J
authors.initials: J
authors.lastname: Petersen
authors.forename: P
authors.initials: P
authors.lastname: Schollmeyer
mesh_terms: D065092:Antidiuretic Hormone Receptor Antagonists; D001127:Arginine Vasopressin / Q000031:analogs & derivatives / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000096:biosynthesis / Q000378:metabolism*; D003894:Deamino Arginine Vasopressin / Q000494:pharmacology; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D006727:Hormone Antagonists / Q000494:pharmacology; D006801:Humans; D007678:Kidney Glomerulus / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010121:Oxytocin / Q000494:pharmacology*; D017483:Receptors, Vasopressin / Q000819:agonists; D012076:Renal Agents / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D065092:Antidiuretic Hormone Receptor Antagonists; D006727:Hormone Antagonists; D017483:Receptors, Vasopressin; D012076:Renal Agents; D001127:Arginine Vasopressin; D010121:Oxytocin; C025043:vasopressin, 1-(1-mercaptocyclohexaneacetic acid)-2-(O- methyl-L-tyrosine)-8-L-arginine-; D000242:Cyclic AMP; D003894:Deamino Arginine Vasopressin; D002118:Calcium