银杏叶提取物对缺氧复氧致神经细胞凋亡中Bcl-2蛋白表达的影响

为探讨缺氧 /复氧致原代培养的大鼠大脑皮层神经细胞凋亡中 Bcl-2的表达及银杏叶提取物的调节作用 ,本实验使用胎龄 16～ 17d Wistar大鼠的大脑皮层神经细胞进行原代分离培养。采用 TUNEL染色方法、透射电镜技术确立缺氧复氧神经细胞凋亡病理模型 ,并应用免疫组织化学方法显示缺氧复氧不同时间 Bcl-2基因的表达。结果显示 :缺氧复氧可使大鼠大脑皮层神经细胞发生凋亡 ,随缺氧时间的延长 ,凋亡细胞数渐多 ,至缺氧 8h,复氧 18h达高峰 ,银杏叶提取物预保护可使凋亡细胞数减少 ;随缺氧时间延长 ,Bcl-2表达逐渐下降 ,银杏叶提取物可逆转缺氧复氧时 Bcl-2的表达。结果提示 ,银杏叶提取物对缺氧复氧时Bcl-2表达具有明显的抑制作用 ,这种抑制作用可能是银杏叶提取物对抗缺氧复氧时胎鼠大脑皮层神经细胞发生凋亡的机制之一。

THE EFFECT OF EGB ON THE EXPRESSION OF Bcl-2 PROTEIN IN THE APOPTOSIS OF NEURONS FOLLOWING HYPOXIA/REOXYGENATION

To investigate the expression of Bcl-2 protein in the apoptosis of primary cultured rat cortical neurons following hypoxia/reoxygenation(H/R) and the protective role of extract of ginkgo biloba (EGB), the cortical neurons of E16-17 fetal rat were primarily cultured. The apoptosis model of primary cultured cortical neurons following H/R was established by using TUNEL staining and electromicroscopy. The expression of Bcl-2 protein was investigated with immunohistochemical method. H/R could cause apoptosis of primary cultured rat cortical neurons. The apoptotic cell increased with the time, and reached peak value at H8R18; EGB could decrease the percentage of apoptosis. The expression of Bcl-2 protein decreased with hypoxia time, and EGB could inverse the expression of Bcl-2. The above results suggest that EGB can singnificantly inhibit the expression of Bcl-2, which may be the one of the mechanisms of apoptosis.