Effects of Caspase Inhibitor on Fas Ligand Expression Following Myocardial Ischemia-reperfusion

Objective To evaluate the expression of the pro-apoptotic molecule Fas and Fas Ligand(FasL)in normothermic ischemia-reperfusion(I-R)induced apoptosis in rat myocardium treated or not treated with Z-VAD-fmk caspase inhibitor.Methods Rats were divided into three groups:group 1,sham operation;group 2,control,PBS administration;group 3,Z-VAD-fmk treatment.Z-VAD-fmk was injected intravenously 2 min before induction of ischemia.Immunohistochemical detection of apoptotic myocardium cells was carried out using the TUNEL method.Fas and FasL expressions were measured by qualitative reverse transcription polymerase chain reaction(RT-PCR)at different times after reperfusion.Histopathological changes in myocardium were also observed.Results FasL and Fas mRNA expressions were increased in myocardium with ischemia-reperfusion,pre-treatment of rats with Z-VAD-fmk caspase inhibitor reduced myocardium apoptosis,and down-regulated Fas/FasL mRNA levels.Conclusion These results suggest that apoptosis and the pro-apoptotic molecule Fas/FasL system are involved in the process of myocardial ischemia-reperfusion injury.