EFFECT OF ADRENAL MEDULLECTOMY AND TOTAL ADRENALECTOMY ON THE HEMODYNAMIC RESPONSES TO TYRAMINE

¹ Departments of Pharmacology and Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania

Hemodynamic responses to a continuous intravenous infusion of tyramine hydrochloride were measured in trained, unanesthetized dogs. These responses were not modified by adrenal medullectomy or total adrenalectomy. Reserpine, in both the intact and the adrenal medullectomized animals, markedly reduced the response to tyramine, and there was no difference in response between the intact reserpine-treated and the medullectomized reserpine-treated animals. Control values for left ventricular pressure and its first derivative were reduced in totally adrenalectomized dogs, but the response to tyramine was not altered. It is concluded that the hemodynamic responses to an infusion of tyramine are not dependent on the presence of the adrenal cortex or medulla.