Adrenocortical suppression and myocardial infarction in non-arteriosclerotic (virgin) and arteriosclerotic (breeder) rats.

Non-arteriosclerotic, virgin and arteriosclerotic, breeder rats were treated with aniline to suppress adrenal steroidogenic capacity and responsiveness to the stress of acute myocardial infarction. After two weeks of aniline treatment, some of the non-arteriosclerotic and arteriosclerotic animals were given two injections of isoproterenol, spaced 24 h apart, to induce massive myocardial infraction. On the 3 rd day, when myocardial necrosis reaches its zenith, the animals were sacrificed. Aniline-induced adrenal insufficiency caused increased mortality, absence of congestive heart failure, cardiac and adrenal enlargement but no evidence of the characteristic intense catabolism and increased corticoid production which attends acute myocardial infarction. Serum enzymes, e.g., SGOT, SGPT and LDH, triglycerides, but not glucose, free fatty acids and cholesterol, became acutely elevated in animals treated with aniline and isoproterenol. Animals developed a fatty liver, beta cell degranulation, post hypophy-sectomy-like changes in their adrenal cortices, unusually severe infarction, marked distention of intermuscular spaces, frequent foci of dystrophic calcification and cartilaginous metaplasia of the papillary muscles. It is believed that aniline-induced adrenal suppression altered the usual pathophysiologic response to acute myocardial infarction.