Differences in metabolic responses to beta-adrenergic stimulation after propranolol or metoprolol administration.
Isoprenaline, or the beta 2-agonist terbutaline, was infused in healthy male volunteers and the plasma levels of insulin, glucose and free fatty acids (FFA) were determined. Saline, propranolol, or the selective beta 1-receptor antagonist, metoprolol, was administered i.v. prior to the infusion of the beta-stimulants. The two beta-receptor blockers inhibited isoprenaline-induced increase in chronotropy to about the same extent, while the effects on systolic and diastolic blood pressure were in accordance with a selective beta1-blocking effect of metoprolol and a non-selective beta-blocking action of propranolol. Quantitative differences were found between metoprolol and propranolol on the metabolic parameters. The effects can best be described in terms of beta 1- or beta 2-receptors, where effects on plasma FFA and glycerol levels seem to be mainly beta1-mediated. An apparent beta 2-mediated effect was found for insulin release and hepatic glucose output.
D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005990:Glycerol / Q000097:blood; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007328:Insulin / Q000097:blood; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D008790:Metoprolol / Q000494:pharmacology*; D011412:Propanolamines / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology*; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D012965:Sodium Chloride / Q000494:pharmacology; D013726:Terbutaline / Q000494:pharmacology*
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D011412:Propanolamines; D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D012965:Sodium Chloride; D011433:Propranolol; D008790:Metoprolol; D007545:Isoproterenol; D013726:Terbutaline; D005990:Glycerol