beta-blockade, atrial natriuretic peptide and exercise.
Changes in the release of atrial natriuretic peptide (ANP) and vasopressin (VP) may contribute to the final outcome of beta-adrenoceptor blocking therapy. Therefore, we administered 2 hours before a bicycle exercise test (a 30-minute exercise with 100 W work load) in a randomized, double-blind, placebo-controlled crossover study orally 50 mg atenolol, 80 mg propranolol or 10 mg pindolol to 15 healthy volunteers. Hormone release and sympathoadrenal activation were estimated by measuring plasma ANP-, VP-, adrenaline and noradrenaline concentrations. beta-blockade and -antagonism were estimated by measuring the reduction of exercise-induced tachycardia and the extent to which the drugs occupied rabbit lung beta 1- and rat reticulocyte beta 2-adrenoceptors in the circulating plasma. We noticed clear differences in the animal beta 1- and beta 2-receptor occupancy between these agents. The agents and placebo during the exercise augmented plasma ANP level similarly, on average by 34-72%. Pindolol administration enhanced the decline of plasma ANP level after exercise (ANCOVA rep meas, pindolol vs placebo, p < 0.05). Although pindolol increased the mean plasma VP level by 25% (ANCOVA rep meas for the increase, pindolol vs placebo, p < 0.05), drug effects on plasma VP-level were generally negligible. In conclusion, in healthy volunteers beta 1- and beta 2-antagonism by pindolol, atenolol and propranolol do not markedly potentiate plasma ANP- and VP-responses to physical exercise. The responses are, however, slightly influenced presumably by the beta-agonist activity of pindolol.
Kantola
I
I
Department of Medicine, University of Turku, Finland.
Tarssanen
L
L
Scheinin
M
M
Ruskoaho
H
H
Viinamäki
O
O
Kaila
T
T
D000316:Adrenergic alpha-Agonists / Q000097:blood; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000328:Adult; D001262:Atenolol / Q000494:pharmacology; D009320:Atrial Natriuretic Factor / Q000097:blood* / Q000187:drug effects; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004837:Epinephrine / Q000097:blood; D005080:Exercise Test / Q000187:drug effects; D006801:Humans; D008297:Male; D009638:Norepinephrine / Q000097:blood; D010869:Pindolol / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D014667:Vasopressins / Q000097:blood* / Q000187:drug effects
D000316:Adrenergic alpha-Agonists; D000319:Adrenergic beta-Antagonists; D014667:Vasopressins; D001262:Atenolol; D009320:Atrial Natriuretic Factor; D011433:Propranolol; D010869:Pindolol; D009638:Norepinephrine; D004837:Epinephrine