Cell apoptosis,caspase-3 mRNA and protein expression,left ventricular segmental function in acute myocardial ischemia reperfusion:experimental study

Objective To investigate the changes of apoptosis and caspase-3 expression, left ventricular segmental function using strain rate imaging following acute ischemia reperfusion in dogs. Methods Thirty dogs were divided into ischemia (10), reperfusion (10), and control (10) groups. Left anterior descending coronary artery (LAD) were occluded 30 min in ischemia group, dogs in reperfusion group were studied at LAD ligation 30 min, following reperfusion 120 min. Dogs without LAD ligation were used as control group. The left ventricular segmental function were detected by echocardiography using strain rate anlysis software. The percentage of apoptosis in left myocardial dysfunction was detected by terminal deoxynudeotidy transferease-mediated biotinylated deoxyuridine triphosphate nick end labeling (TUNEL). Caspase-3 mRNA and protein expression were analyzed by RT-PCR and immunohistochemistry. Results The peak strain rate (SRpeak) in ischemia group decreased obviously (P0.01), and postsystolic compression (PSC) was found in ischemia segment. SRpeak increased slightly after reperfusion 120 min, but still decreased than control group. The positive cell of TUNEL detected in ischemia myocardial had no difference between ischemia group and control groups, and increased in reperfusion group (P0.05). Caspase-3 mRNA and protein expression increased more significantly in ischemia group than that in control group. And significantly increased in reperfusion group (P0.01). Conclusion Caspase-3 expression and cell apoptosis may be the early changes following acute ischemia reperfusion in dogs, which are related to the left ventricular segmental function.