Effect of 10 Weeks Aerobic Exercise Training on Left Ventricular Systolic Function, Caspase-3 and Infarction Size in Myocardial Infarction Rat

The aim of the present study was to evaluate the effect of 10 weeks of aerobic exercise training on left ventricular systolic functioning in myocardial infarction rats. Four weeks after the surgical procedures, 30 male Wistar rats were randomized to the following groups: Sham-operated control (Sham); Sedentary-MI (SedMI); Exercise-MI (ExMI); the rats were subjected to aerobic training in the form of treadmill running (50 min/day, 5 times per week, 17 m/min). Before and after the training program, all subjects underwent resting echocardiography. Statistical analysis of the data showed that the rate of ejection fraction and the fractional shortening at 4 and 14 weeks after myocardial infarction decreased significantly in SedMI and ExMI in compare to the Sham group (P<0.05). But the rate of ejection fraction and fractional shortening at 14 weeks after myocardial infarction in ExMI group was significantly greater than SedMI group (P<0.05). Also, infarction size and mortality decreased significantly in response to exercise training but the caspase-3 activity was not different between groups. 10-week aerobic exercise training program, 4 weeks after myocardial infarction, reduced cardiac dysfunctions after myocardial infarction in trained rats. Consequently, these exercise training induced changes resulted in improved left ventricular systolic functional and decrease of mortality and infarction size after myocardial infarction.