THE EFFECT OF ACUTE AND CHRONIC ADMINISTRATION OF RESERPINE ON THE RESPIRATION OF RAT AORTA

¹ The Department of Physiology and Pharmacology, University of Alberta, Edmonton, Canada

The respiration of isolated rat aorta, measured by the Warburg direct technique, was unaffected by the daily administration of reserpine in doses of 0.1 mg/kg for 10 days or 1.0 mg/kg 20 hours before sacrifice. Aortic respiration was depressed, however, after 10 daily doses of 0.5 mg/kg or 5.0 mg/kg reserpine either 20 hours or 4 hours before measurement. The reduced aortic QO₂ following the higher chronic dose may be explained by a general depression of the metabolism of the animals. Such an explanation is less acceptable in the case of rats treated with the higher acute dose, either 20 or 4 hours before killing. It is suggested therefore, that in these cases, the effect of reserpine on aortic respiration is more specific. These findings, together with previous observations may point to an effect of reserpine on oxidative metabolism in aortic smooth muscle.