ANTIARRHYTHMIC PROPERTIES OF MJ9067 IN ACUTE ANIMAL-MODELS

Abstract

A novel benzanilide derivative, MJ 9067 (4-methoxy-2''-[2-(1-methyl-2-piperidyl)-ethyl]benzanilide), abolished experimental atrial and ventricular arrhythmias effectively and promoted the return of normal sinus rhythm in a variety of animal models. At i.v. dose levels ranging from 0.5-3.2 mg/kg, MJ 9067 successfully converted atrial fibrillation induced by either local application of aconitine or electrical stimulation, and ventricular tachycardia elicited by i.v. injection of ouabain or digoxin. The compound was equally effective in vagotomized or nonvagotomized dogs, and in intact cats and [squirrel] monkeys. The ventricular ectopic rate in conscious dogs 18-20 h after 2-stage ligation of a coronary artery was also markedly reduced by the drug at 2 mg/kg i.v. At antiarrhythmic dose levels, there were no undesirable effects noted on peripheral blood pressure, heart rate or the configuration of the ECG.