Glucagon-sensitive adenylate cyclase in human renal medulla.
In cell-free preparations (washed 600 x g pellets) of human renal medulla, glucagon produced a dose-dependent stimulation of adenylate cyclase. The stimulation of renal medullary adenylate cyclase by saturating concentrations of glucagon was additive to the saturating doses of vasopressin. Furthermore, L-isoproterenol stimulated renal medullary adenylate cyclase in a dose-dependent manner, and this stimulation was blocked by DL-propranolol. Stimulation of the renal medullary adenylate cyclase by maximal doses of glucagon and L-isoproterenol was additive. DL-Propranolol did not inhibit stimulation of glucagon. Thus, the results indicate the existence of a specific adenylate cyclase that is responsive to glucagon--distinct from the isoproterenol-sensitive adenylate cyclase and the previously described vasopressin-sensitive adenylate cyclase in human renal medulla. We suggest that the renal tubular effect of glucagon may be mediated by glucagon-dependent cyclic-AMP production in renal tissue.
D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000318:Adrenergic beta-Agonists / Q000378:metabolism; D001127:Arginine Vasopressin / Q000494:pharmacology; D000242:Cyclic AMP / Q000096:biosynthesis / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004573:Electrolytes / Q000378:metabolism; D005934:Glucagon / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D007668:Kidney / Q000201:enzymology*; D007679:Kidney Medulla / Q000201:enzymology*; D011433:Propranolol / Q000494:pharmacology; D014867:Water / Q000378:metabolism
D000067956:Adenylyl Cyclase Inhibitors; D000318:Adrenergic beta-Agonists; D004573:Electrolytes; D014867:Water; D001127:Arginine Vasopressin; D005934:Glucagon; D011433:Propranolol; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D007545:Isoproterenol