银杏叶提取物后处理对大鼠局灶性脑缺血再灌注损伤保护作用的研究

目的 探讨银杏叶提取物EGb761对大鼠局灶性脑缺血再灌注损伤的保护作用及其机制.方法 制作大鼠右侧大脑中动脉闭塞再灌注模型.将30只清洁级雄性SD大鼠随机分为3组,即假手术组（n-10）：给予5 ml生理盐水腹腔注射;对照组（n-10）：缺血90 min,再灌注24 h,5 ml生理盐水腹腔注射;实验组（n-10）：缺血90 min,再灌注24 h,在再灌注即刻20 mg/kg银杏叶提取物生理盐水稀释成5 ml腹腔注射.再灌注24 h后采用四分法测定大鼠的神经功能障碍评分（NDS）;实验结束后断头取脑采用TTC染色法测定脑梗死面积（以其同侧大脑半球体积的百分比表示）;采用western blot测定脑组织微管相关蛋白2（MAP2）的表达水平.结果 与假手术组比较,对照组、实验组小鼠NDS评分均显著升高,分别为（2.49±0.85）分和（1.58±0.62）分,3组间比较差异均明显（P＜0.05）;对照组、实验组脑梗死面积均显著增大（P＜0.05）,实验组脑梗死面积较对照组显著减小（P＜0.05）;与假手术组比较,与假手术组比较,对照组、实验组缺血侧MAP2蛋白的表达水平均显著降低（P＜0.05）,实验组缺血侧MAP2蛋白的表达水平较对照组显著升高（P＜0.05）.结论 银杏提取物EGb761对大鼠局灶性脑缺血再灌注损伤具有显著的保护效应,其效应与MAP2蛋白表达水平升高有关.

Neuroprotective effects of extract of Ginkgo biloba postconditioning on the focal cerebral ischemia reperfusion injury in rats

Objective To explore neuroprotective effects and possible mechanisms of extract of Ginkgo biloba postconditioning on the focal cerebral ischemia reperfusion injury in rats.Methods 30 adult male SD rats were randomly divided into 3 groups （n-10）：sham：normal saline intraperitoneal injected; Control group：cerebral ischemia 90 min,reperfusion 24 h,normal saline intraperitoneal injected; Experiment group：cerebral ischemia 90 min,reperfusion 24 h,rats were intraperitoneal injected 20 mg/kg of ginkgo biloba dilu ted 5 ml in immediate reperfusion.The model of right middle cerebral artery occlusion（MACO） and reperfu sion was made.At 24 hour after reperfusion,the neurologic deficit scores（NDS） were evaluated using a four point scale.At the end of 24 h reperfusion,the rat were anesthetized and sacrificed by decapitation.The brains were rapidly removed for measuring the cerebral size（n-5）and the expression of MAP2 （n-5）.The cerebral infart size was expressed as a percentage of the area at ipsilateral hemisphere.Results 1 NDS：com pared with sham group,NDS values in group control group and experiment group increased significantly（P＜ 0.05）,compared with control group,NDS values significantly decreased in experiment group （P＜0.05）.In farct size：compared with sham group,the infarct size in control group and experiment group increased signifi cantly（P＜0.05）,compared with control group,the infarct size significantly decreased in experiment group（P ＜0.05）.MAP2 expression：the expression of MAP2 in ipsilateral hemisphere significantly decreased in control group and experiment group（P＜0.05）.compared with control group,the expression of MAP2 in ipsilateral hemisphere significantly increased in experiment group（P＜0.05）.Conclusions Ginkgo biloba extract postcon ditioning on focal cerebral ischemia reperfusion injury in rats has significant neuroprotective effects,which highly correlate with the increased expression of MAP2.