The haemodynamic and metabolic effects of MG 8926, a prospective antidysrhythmic and antianginal agent.

1 The antidysrhythmic, haemodynamic and metabolic effects of a new prospective antianginal and antidysrhythmic agent, N-(3-3-dipenylpropyl)-alpha-methyl-beta-cyclohexylethylamine hydrochloride (MG 8926), have been compared with the chemically related substance, prenylamine, in anaesthetized greyhounds and guinea-pigs. 2 When given intravenously 20 min beforehand, both MG 8926 and prenylamine (5 mg/kg) significantly suppressed the early dysrhythmias induced by coronary artery ligation in anaesthetized greyhounds. At a dose of 1 mg/kg, MG 8926 also protected anaesthetized guinea-pigs from dysrhythmias induced by ouabain infusions. 3 In dogs pretreated with MG 8926, metabolic changes indicative of myocardial ischaemia (increased PCO2 and potassium efflux, decreased oxygen content and pH) were less marked than those occurring in control animals. 4 Evidence was obtained that MG 8926, when given either before or after coronary occlusion, was capable of decreasing the severity of myocardial ischaemia as assessed by ST-segment changes in epicardial electrocardiograms.