腹腔注射银杏叶提取物促进大鼠视神经钳夹伤后视网膜神经节细胞存活

目的探讨银杏叶提取物GBE50（Ginkgo biloba extract 50）对大鼠视神经钳夹伤后视网膜神经节细胞（RGCs）的保护作用。方法65只SD大鼠随机等分为正常对照组、假手术组、模型组、模型＋生理盐水（NS）组、模型＋GBE 50组，每只鼠的右眼用于实验。正常对照组不作任何处理；假手术组仅分离暴露视神经；其余3个组分离暴露视神经并进行钳夹：模型＋NS组和模型＋GBE 50组分别于实验前1周每日腹腔注射相应体积NS和0．35％GBE 50（100mg／kg），术后继续给药4周；术后4d，各组随机处死3只大鼠作凋亡RGCs的TUNEL荧光标记；术后4周后处死所有大鼠作光镜检查并计数视网膜垂直经线RGCs。结果正常对照组和假手术组未见TUNEL阳性RGCs；其余3组均见TUNEL阳性RGCs，但模型＋GBE 50组较前两组少。术后4周RGCs数目：模型组（131±10个）、模型＋NS组（137±13个）、模型＋GBE 50组（198±15个）均少于正常对照组和假手术组（P〈0．05）；模型组与模型＋NS组差异无统计学意义（P〉0．05）；但模型＋GBE 50组显著多于模型组和模型＋NS组（P〈0．05）。结论腹腔注射银杏叶提取物GBE 50能部分抑制大鼠视神经钳夹后RGCs凋亡，具有一定的RGCs保护作用。

Intraperitoneal administration of Ginkgo biloba extract (GBE 50) promotes the survival of retinal ganglion cells after crush of intraorbital optic nerve in rats

Objective To investigate the protective effect of Ginkgo biloba extract 50 （GBE 50 ） on retinal ganglion cells （RGCs） after crush of intraorbital optic nerve. Methods Sixty- five Sprague - Dawley （SD） rats were randomly into five groups such as normal control group, sham operation group, model ＋ norreal solution （NS） group and model ＋ GBE 50 group, each consisting 13 rats. In each group, only the tight eyes were used. No operation was carried out in normal control group and the optic nerves were exposed merely in sham operation group. In model group, intraorbital optic nerves were crushed for 10 seconds at 1.0 mm from posterior pole. Corresponding volume of NS or 0. 35% GBE 50 （100 mg/kg） was injected intraperitoneally into the rats fiom 1 week before crush until 4 weeks after crush in model ＋ NS group or model ＋ GBE 50 group. Three rats were sacrificed for analysis of apoptotic RGCs on the fourth day after operation and 10 rats for histological analysis and calculation of the number of RGCs at the tburtb week. Results No TUNEL-positive RGC was noticed in normal control group or sham operation group. A lot of TUNEL- positive RGCs were noticed in model group, model ＋ NS group and model ＋ GBE 50 group; but the number of TUNEL-positive RGCs in model ＋ GBE 50 group was significantly less than that in model and model ＋ NS groups. There was no statistical significance in the number of RGCs between normal control group （331 ± 15） and sham operation group （315 ±21 ） （ P 〉 0.05 ） ; but their number was more than that in model group （131 ±10）, model ＋ NSgroup （137±13） and model ＋ GBE50group （198±15） （P 〈0.05）. Meanwhile, the number of RGCs in model ＋ GBE 50 group was more than that in model group and model ＋ NS group, respectively （P 〈 0.05 ）. Conclusion GBE 50 injected intraperitoneally partly inhibits the apoptosis of RGCs, and promotes the survival of RGCs after crush of intraorbital optic nerve.