Protective effects of ischemic preconditioning on myocardial ischemia reperfusion injury

To investigate the delayed protective roles of ischemic preconditioning on myocardial ischemia reperfusion injury (MIRI) in rats and its possible mechanisms. A total number of 30 rats were randomly divided into 3 groups (n=10) including sham operated group (SHAM), ischemia reperfusion group (I/R) and delayed ischemic preconditioning group (DIPC). Several important hemodynamic parameters were continuously measured and reperfusion arrhythmia was recorded; Levels of serum MDA, cTnI and CK-MB were detected; Activities of SOD, CAT and GSH-Px in serum were also determined. Compared to I/R group, an improved cardiac hemodynamics and a decreased occurrence of reperfusion´s arrhythmia were observed in DIPC group. Levels of serum MDA, cTnI and CK-MB were all decreased, and the activities of serum SOD, CAT and GSH-Px were both elevated in DIPC group. DIPC could have the protective effects on MIRI through increasing the activities of antioxidant enzymes and alleviating damages of oxygen free radials on myocardium.