title: Effect of acebutolol on plasma catecholamine concentrations in anesthetized dogs with ouabain-induced arrhythmias and its direct actions in vitro on the adrenal medulla.
abstract: We have performed studies on blood hormone dynamics following intravenous administration of acebutolol, a newly synthesized beta-blocker, and its direct action on the adrenal medulla in vitro. Intravenous injection of acebutolol into anesthetized dogs almost doubled the plasma adrenaline and noradrenaline concentrations within 5 to 15 minutes, while renin activity was reduced to approximately two-thirds of the pre-administration level. When arrhythmia was induced in dogs with ouabain, the plasma adrenaline and noradrenaline levels increased to 220 +/- 109 and 392 +/- 84 pg/ml, respectively, from the basal levels of 44 +/- 24 and 140 +/- 43 pg/ml. The restoration of sinus rhythm following the administration of acebutolol was accompanied by a further increase in the plasma adrenaline and noradrenaline levels to 797 +/- 364 and 1226 +/- 263 pg/ml, respectively. A perifusion experiment indicated that acebutolol directly accelerated catecholamine release from the adrenal medulla in pigs.
mesh_terms: D000070:Acebutolol / Q000494:pharmacology*; D000313:Adrenal Medulla / Q000187:drug effects*; D000758:Anesthesia; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000097:blood* / Q000188:drug therapy; D002395:Catecholamines / Q000097:blood*; D004285:Dogs; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D010042:Ouabain / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D012083:Renin / Q000097:blood
chemical_list: D002395:Catecholamines; D010042:Ouabain; D000070:Acebutolol; D011433:Propranolol; D012083:Renin