银杏叶提取物改善AD模型鼠学习记忆功能的作用

目的 :研究银杏叶提取物 (EGb)对早老性痴呆 (AD)模型鼠学习记忆等认知功能的影响和对基底前脑隔区胆碱能神经元的保护作用。方法 :大鼠随机分成预防组、治疗组和对照组。各组切割右侧海马伞后分别用EGb(预防组及治疗组 )和蒸馏水 (对照组 )灌胃连续 6周。其中预防组在手术前先用EGb灌胃 2周。各组在术后次日及灌胃 6周后进行行为学检测。脑切片经Nissl、NOS组织化学和ChAT免疫组织化学染色 ,观察损伤侧内侧隔核和斜角带垂直支中NOS和ChAT阳性神经元的变化 ,并对ChAT阳性神经元作图像分析。数据分别用方差分析、SNK检验及 χ2 检验作统计学处理。结果 :行为学检测证实 ,EGb用药组AD模式鼠的学习记忆等认知功能较对照组明显改善 ,其中预防组效果又较治疗组为好 ;形态学检测证实 ,EGb用药组AD模式鼠损伤侧内侧隔核和斜角带垂直支中NOS、ChAT阳性神经元数目及ChAT阳性神经元的面积和周径等均优于对照组 ,预防组结果又优于治疗组。结论 :EGb对AD模型鼠学习记忆等认知功能障碍有一定的改善作用 ,这一作用是通过保护基底前脑隔区胆碱能神经元而实现的 ,其中预防效果比治疗效果更优

Role of Ginkgo Biloba Extracts in Improving the Learning and Memorizing Ability in AD Model Rats

Objective:To study the effects of Ginkgo biloba extracts (EGb) in improving the learning and memorizing ability and protecting the survival of septal area cholinergic neurons in AD model rats. Methods:Rats were grouped randomly into pretreatment,treatment and control.After right side hippocampal fimbrial transection,EGb (pretreatment and treatment group) and distilled water (control group) were respectively forced down into the stomach of the rats for 6 weeks.But in pretreatment group,the rats were treated with EGb for 2 weeks before the operation.Step-through passive avoidance and active avoidance tests were carried out immediately after the leision and 6 weeks later.Brain sections were stained with Nissl,NOS histochemistry and ChAT immunohistochemistry.The changes of NOS and ChAT positive neurons of medial septum and vertical limb of Broca's diagonal band in the ipsilateral side of the fimbrial transection were observed and ChAT postitive neurons were analyzed quantitatively with computer imange system.All the data were statistically analyzed with ANOVE,SNK test and chi-square test.Results:The behavioral tests indicated that the cognitive function of the rats with EGb treatment was improved more obviously than that of the rats with distilled water and the improvement in pretreatment group was superior to that in treatment group.The morphological observations demonstrated that the number of NOS and ChAT positive neurons,and the cell size and circumference of ChAT positive neurons in the ipsilateral side of the fimbrial transection of the rats with EGb treatment were also superior to those of the rats with distilled water,and the data of pretreatment group were better than those of treatment group.Conclusion:EGb can promote the cognitive function of AD model rats by protecting septal area cholinergic neurons and the results of pretreatment group was more effective than those of treatment group.