Interaction Between Thyroxine and Dibenzyline on Metabolic Rate

¹ From the Department of Physiology, University of Illinois College of Medicine, Chicago, Illinois

Doses of Dibenzyline adequate to block the pressor effect of epinephrine were administered to rats with various degrees of chronic hypo- or hyperthyroidism. Rate of oxygen consumption was measured under barbiturate anesthesia. Dibenzyline decreased or did not change hypothyroid metabolic rates, but increased metabolic rates in hyperthyroid rats. The data indicated that Dibenzyline exerts a synergistic effect with thyroxine on metabolism resembling the previously reported synergism between thyroxine and epinephrine. Apparently discrepant findings presented in the literature regarding the interaction of thyroxine and Dibenzyline probably result from differences in the thyroid status of the experimental animals.