[Effects of exercise on coronary circulation in left ventricular hypertrophy caused by hypertension]

Exercise is known to promote myocardial vascularity. We therefore studied whether it could prevent coronary abnormalities of hypertensive left ventricular (LV) hypertrophy. Female Sprague-Dawley 1 clip-2 kidneys Goldblatt hypertensive rats (RHR) and their appropriate controls (Sham-SH), were either made to swim (RHR-SW, SH-SW) or kept sedentary (RHR-SED, SH-SED) for 9 weeks. Maximal coronary blood flow (LV CBF, ml/min/gm) and minimal coronary resistance after carbochrome (total LVCR/LV mmHg/ml/min), an index of the functional cross sectional area (CSA) of coronary resistance vessels, were determined in conscious rats by microspheres. Results (m +/- SD) (n = 12 in all groups): (Table: see text). Exercise increased functional coronary CSA in normotensive rats only. This beneficial effect did not occur in hypertension, probably because of functional changes in the coronary vessels of RHR.