Effects of salbutamol and butoxamine on the human fat cell adenylate cyclase.
In order to characterize the beta-adrenoceptors coupled to the human fat cell adenylate cyclase more extensively the effects of the beta 2-selective agonist salbutamol on basal and isoproterenol-stimulated rates of cAMP-accumulation were studied. Although exhibiting only low intrinsic activity salbutamol displayed only slightly lower affinity towards the beta-adrenoceptors linked to the human fat cell adenylate cyclase than isoproterenol. In addition, the beta 2-selective antagonist butoxamine was slightly more potent in inhibiting the isoproterenol-stimulated fat cell enzyme than the cardioselective beta-blocking agent practolol. These results further emphasize the difficulties in classifying the lipolytic response of adipose tissue to beta-adrenergic agonists and antagonists within a uniform beta-receptor theory.
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000273:Adipose Tissue / Q000187:drug effects / Q000201:enzymology*; D000420:Albuterol / Q000494:pharmacology*; D002078:Butoxamine / Q000494:pharmacology*; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D011217:Practolol / Q000494:pharmacology; D011412:Propanolamines / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D013379:Substrate Specificity
D011412:Propanolamines; D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D002078:Butoxamine; D011433:Propranolol; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D007545:Isoproterenol; D000420:Albuterol; D011217:Practolol