ACUTE OR CHRONIC EXERCISE ALTERS ANGIOTENSIN-II-INDUCED CONTRACTION OF RAT AORTA

Chronic exercise substantially shifted the dose-response curve for ang iotensin II (ANG II)-induced contractions to the right with increases in the EC(50) value in both endothelium-intact and endothelium-denuded aortae. An acute endurance exercise also caused a 3-fold increase in the EC(50) value in both endothelium-intact and endothelium-denuded ao rtae from sedentary control rats, Whereas, no substantial increase in the EC(50) value was observed in trained rats after an acute endurance exercise. Thus, chronic exercise attenuates ANG II receptor-mediated contraction of rat aortae. An acute exercise also caused the reduced r esponses to ANG II in sedentary control rats but not in chronically ex ercise-trained rats.