Pravastatin decreases infarct size induced by coronary artery ischemia/reperfusion with elevated eNOS expression in rats

Abstract

Our previous study showed that pravastatin prevents ischemia and reperfusion-induced lethal ventricular fibrillation in rats. This study explored whether pravastatin decreases myocardial infarct size and this effect is associated with endothelial nitric oxide synthase (eNOS) expression in myocardium. Rats were treated with ischemia (30 minutes) and reperfusion (60 minutes) after chronic oral administration of pravastatin, fluvastatin, or vehicle once daily for 22 days. Electrocardiograms and blood pressure were continuously recorded, myocardial infarct size was measured by TTC-staining, and eNOS expression was measured by western blot. The results showed that pravastatin and fluvastatin significantly reduced myocardial infarct size. No statistical differences were found in the areas at risk among all groups. However, a significant reduction in infarct size was observed in three pravastatin groups and one fluvastatin group compared to control. Both pravastatin and fluvastatin significantly increased eNOS protein expression in ischemic and non-ischemic tissues compared to control. Our results suggest that pravastatin decreases cardiovascular mortality beyond its cholesterol-lowering effect. Pravastatin is more potent than fluvastatin in reducing infarct size. These effects may be associated with elevation of eNOS expression.