Abstract: Objective To observe the effect of NGF on the caspase-12 in cerebral ischemia-reperfusion, and elucidate the protective mechanism of NGF on cerebral tissue underwent ischemia-reperfusion in rabbit. METHODS Twenty-six healthy male white rabbits weighting （2.6±0.2）kg were randomly divided into sham operation group, ischemia-reperfusion group and NGF group. The tissues of ischemia-reperfusion region were taken to detect the expression of caspase-12, caspase-3 by immunohistochemistry and to analyze them with Motic 6.0 image analysis system, and to detect the I/R cerebral apoptosis by flow cytometry and TUNEL staining methods. RESULTS The caspase-12 and caspase-3 expresses in a low level, a few apoptotic cells were detected by FCM and the TUNEL staining in sham operation group. As compared with that in sham operation group, the expression of caspase-12 and caspase-3 in I/R group and NGF group were higher (P<0.01); the apoptotic cells detected by FCM and TUNEL methods were significantly increased, as compared with those of sham operation group(P<0.01). As compares with those of I/R group, the levels of caspase-12 and caspase-3 in NGF group were lower than that of I/R group, the percentage of apoptotic cells was lower than that of I/R group (P<0.01). CONCLUSION NGF can decrease the number of apoptotic cells of the cerebral ischemia-reperfusion, inhibit the caspase cascade reaction induced by caspase-12, which is one of the protective mechanisms of NGF.

Key words: Nerve growth factor(NGF), cerebral ischemia reperfusion injury, caspase-12, apoptosis