CORNARY VASODILATORS ON MYOCARDIAL OXYGEN CONSUMPTION AND AMMONIA PRODUCTION

Four coronary vasodilators were investigated in 18 canine heart-lung preparations. The two organic nitrates ipentaerythrityl tetranilrate and glyceryl trinitrate) caused an increase in coronary blood flow, an increase in myocardial efficiency and an increase in production of ammonia by the heart muscle. On the other hand, dipyridamole and intensain caused a decrease in production of ammonia. These effects were elicited in response to increase in cardiac work imposed by cither elevation in venous reservoir or increase in pressure load in the aorta. © 1968 S. Karger AG, Basel.