Actions of bretylium tosylate on the cardiovascular system of the dog

Abstract

AUTHORS' SYNOPSIS: Bretylium tosylate produced an increase in myocardial contractility and heart rate in the dog. These actions were blocked by propranolol and by reserpine pretreatment. The drug also produced an initial transient vasodilatation which was blocked by atropine and was followed by a more sustained rise in blood pressure. This pressor response was partially blocked by phentolamine and reserpine pretreatment. It is concluded that the cardiac actions of this drug are indirect, due to catecholamine release.