COMPARISON OF CARDIOTOXIC ACTIONS OF CERTAIN SYMPATHOMIMETIC AMINES

Abstract

Rats were injected subcutaneously on 2 consecutive days with various doses of four sympathomimetic amines. The doses chosen were the median lethal dose or fractions thereof. The animals were sacrificed at 48 hours and myocardial lesions were graded in the gross and after histological sectioning. A synthetic adrenergic agent, isoproterenol, was found to cause severe infarct-like myocardial necrosis. The lesions which were seen after isoproterenol treatment were more severe than those produced by l-epinephrine, l-arterenol, or ephedrine. This was the case whether the severity of the lesions was expressed in terms of single dose lethality of the compound or in terms of absolute amount. It was concluded that the myocardial lesions produced by these drugs are related to their cardiac stimulant properties.