title: Effect of atrial natriuretic polypeptide on angiotensin II-induced increase of cytosolic free calcium in cultured smooth muscle cells.
abstract: We investigated the effects of angiotensin II (ANG II) and synthetic atrial natriuretic polypeptide (ANP) on cytosolic free calcium concentration [( Ca2+]i) of cultured rat vascular smooth muscle cells. Incubation with ANP alone showed little or no change in [Ca2+]i, whereas ANG II alone increased [Ca2+]i in a dose-dependent manner up to 164%, compared with basal levels of 253 +/- 17 nmol/l (mean +/- s.e.m.). Simultaneous addition of 10 nmol/l ANG II and varying concentrations of ANP produced a reduction in the ANG II-induced increase in [Ca2+]i. These data suggest that the vasorelaxant effect of ANP is at least partly mediated by changes in [Ca2+]i.
mesh_terms: D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D003600:Cytosol / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D013268:Stimulation, Chemical
chemical_list: D000804:Angiotensin II; D009320:Atrial Natriuretic Factor; D002118:Calcium