Cyclic AMP-dependent phosphorylation of a 16 kDa protein in a plasma membrane-enriched fraction of rat aortic myocytes.
Phosphorylation induced by cAMP-dependent protein kinase was examined in a plasma membrane-enriched fraction from control and beta-adrenergic-stimulated rat aortic myocytes. Phosphorylation of a 16 kDa protein which copurified with the plasma membrane marker (Na+ + K+)-ATPase was most prominent. It was decreased by pretreatment of the myocytes with isoproterenol and the effect of isoproterenol was inhibited by propranolol. Both phosphorylation induced by cAMP-dependent protein kinase and its inhibition by isoproterenol pretreatment declined in preparations exposed to endogenous phosphatase. These results provide strong evidence that beta-adrenergic stimulation of aortic myocytes induces in situ phosphorylation of a 16 kDa plasma membrane protein.
D000818:Animals; D001011:Aorta / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D005260:Female; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000037:antagonists & inhibitors / Q000494:pharmacology; D008565:Membrane Proteins / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D010766:Phosphorylation; D011433:Propranolol / Q000494:pharmacology; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D008565:Membrane Proteins; D011433:Propranolol; D011494:Protein Kinases; D007545:Isoproterenol