Protective Effects and Underlying Mechanism of Nicorandil on Cardiac Function in Rats with Ischemic Heart Failure

Purpose: To evaluate the effects of nicorandil on cardiac function in rats with ischemic heart failure and explore the underlying mechanism of those effects.
Methods: Adult Sprague Dawley (SD) rats were randomly divided into 3 groups: the nicorandil (n=9) and control (n=9) group animals underwent ligation of the left anterior descending coronary artery; the sham operation group animals (n=6) underwent chest opening without coronary artery ligation. The nicorandil group animals were administered nicorandil orally, and the animals in the other groups were administered saline orally. Eight weeks after operation, cardiac function was assessed in each animal by blood pressure measurement and ultrasonic cardiography. In addition, left ventricle to body weight ratio (LVW/BW) was calculated. Myocardial tissue was examined by HE staining and immunohistochemistry to assess morphological changes and Bax levels, respectively.
Results: Systolic blood pressure was higher in the control group than in the nicorandil group (P<0.05). Left ventricular ejection fraction was lower in the controls than in the nicorandil-treated rats, and the sham animals had the highest left ventricular ejection fraction values (P<0.05). In addition, the E/A ratio was lower and LVW/BW was significantly higher in the control group than in the nicorandil group (P
Conclusion: Nicorandil decreases Bax protein expression and inhibits apoptosis in myocardial cells, and these effects improve left ventricular ejection fraction and cardiac function.