[Effects of cyclosporine A on pneumocyte apoptosis with lung ischemia/reperfusion injury in rats].

Objective:To investigate the effects of cyclosporine A(CsA), a powerful inhibitor of mitochondrial permeability transition pore(MPTP), on pneumocyte apoptosis, the release of cytochrome C and the activity of caspase-3 after lung ischemia/reperfusion, and explore the mechanisms. Methods: Single lung in situ ischemia/reperfusion animal model was used. 30 SD rats were randomly divided into three groups(n=10): sham (S) group, ischemia/reperfusion (I/R) group and cyclosporine A(CsA) group. Apoptosis of pneumocyte was assessed by TUNEL method, cytochrome C(CytC) in cytoplasm was detected by immunohistochemistry techniques, and the activity of caspase-3 was measured with spectrophotometer. Results: The content of CytC in cytoplasm, the activity of caspase-3,and the value of apoptosis index (AI) in ischemia/reperfusion group were evidently higher than that in S group(P0.01 ). CsA suppressed apoptosis as well as CytC release and caspase-3 activity(P0.01). Conclusion: CsA can prevent the release of cytochrome C, block the apoptosis of pneumocyte accordingly maybe by closing the MPTP.