Relationship of caspase-3 activity and cardiac function in rat cardiomyocytes after myocardial reperfusion injury

Objective To investigate the correlation between caspase-3 and left ventricular function at different phases after ischemia-reperfusion. Methods Totally 36 wistar rats were randomly divided into Sham operation group and ischemia-reperfusion(IR)group. The rat ischemic cardiac region of IR group was taken after 1, 3, 6, 12 and 24-hour reperfusion followed to 30-minute ischemia and detected for the activity fragment of caspase-3 P20, the activity of caspase-3, myocardial apoptosis index, left ventricular function (LVF) and creatine kinase-MB (CK-MB) respectively. Results With reperfusion time prolonging, the activity fragment of caspase-3 P20 increased, the activity of caspase-3, myocardial apoptosis index, left ventricular function and CK-MB all changed. The activity fragment of caspase-3 P20 and CK-MB peaked at 6 h, and the activity of caspase-3 and myocardial apoptosis index at 12 h, and then maintained platform; LVSP and ±dp/dt_max increased while LVEDP decreased gradually with the reperfusion time prolonging. All indexes mentioned above of IR group had statistical significance as compared with that of Sham operation group(P0.05,P0.01). Conclusion The activation of caspase-3 may be one of the mechanism of heart function descent resulting from myocardial apoptosis after myocardial ischemia-reperfusion.