title: Actions of atrial natriuretic peptide (ANP) on cyclic nucleotide concentrations and phosphatidylinositol turnover in ventricular myocytes.
abstract: Atrial natriuretic peptide (ANP) stimulates cGMP production in isolated rabbit ventricular myocytes incubated in the presence of the phosphodiesterase inhibitor isobutylmethylxanthine (1mM). Half maximal activation was found at 10(-8)M ANP. Cellular cGMP concentrations of around 0.6 pmol/10(6) cells were elevated 4-6 fold by ANP (10(-6)M), 3-4 fold by carbachol (1mM) and around 10 fold by sodium nitroprusside (1mM). ANP had no effect on basal or isoprenaline-stimulated cAMP concentrations or on basal or noradrenaline-stimulated turnover of phosphatidylinositol. From these results we conclude that ANP receptors, coupled to particulate guanylate cyclase, exist in cardiac ventricular muscle. This indicates that ANP may also have a physiological action on ventricular muscle contractility during volume expansion.
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002217:Carbachol / Q000494:pharmacology; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D007295:Inositol Phosphates / Q000378:metabolism; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D009599:Nitroprusside / Q000494:pharmacology; D009712:Nucleotides, Cyclic / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000378:metabolism*; D011433:Propranolol / Q000494:pharmacology; D011817:Rabbits
chemical_list: D007295:Inositol Phosphates; D009712:Nucleotides, Cyclic; D010716:Phosphatidylinositols; D009599:Nitroprusside; D009320:Atrial Natriuretic Factor; D002217:Carbachol; D011433:Propranolol; D007545:Isoproterenol; D015056:1-Methyl-3-isobutylxanthine