Cardiac actions in the dog of a new antagonist of adrenergic excitation which does not produce competitive blockade of adrenoceptors.

摘要: Summary 1 The cardiac actions of amiodarone, a benzofuran derivative used in the treatment angina pectoris, have been compared with those (±)-propranolol anaesthetized dogs. 2 After three successive intravenous injections propranolol, 0·5 mg/kg, had reduced heart rate by 25%, fourth dose no further negative chronotropic action, but 10 mg/kg intravenously, at this point 23%. 3 Amiodarone, reduced, did not abolish, responses to isoprenaline, 2 μg/kg intravenously. Subsequent amiodarone block 1 abolished them. 4 Amiodarone and inotropic glucagon, which were affected propranolol. 5 Cardiac output was increased 5 min after thereafter it differ from control values. Propranolol, 17% min, 30% 30 min. 6 From other evidence is discussed, concluded that are produced competitive blockade β-adrenoceptors.