银杏叶提取物对点燃模型幼鼠学习记忆及海马乙酰胆碱酯酶、胆碱乙酰转移酶活性的影响

目的研究银杏叶提取物（EGb）对点燃模型幼鼠学习记忆等认知功能，对大鼠海马乙酰胆碱酯酶（AChE）、胆碱乙酰转移酶（ChAT）活性的影响。方法21、35日龄SD大鼠各40只，经初筛后随机分为生理盐水对照组、点燃对照组及EGb大、中、小剂量治疗组，采用戊四氮（PTZ）诱导幼鼠点燃模型，以Y型电迷宫及生化检测方法，观察用药前后大鼠学习记忆功能和海马AChE、ChAT活性的变化。结果EGb呈剂量依赖性显著改善实验大鼠的学习记忆能力，并显著抑制海马AChE活性、增强ChAT的活性。结论EGb可以通过抑制功能脑区AChE活性、增加ChAT的活性，增强中枢胆碱能神经系统的功能，改善发育期癫痫大鼠学习记忆功能。

Effect of extracts of Ginkgo biloba leaf on the learning-memory ability and the activity of AChE and ChAT in the hippocampus in rats with kindling-induced epilepsy

Objective To investigate the effects of extracts of Ginkgo biloba leaf （EGb） on the cognitive functions such as learning and memory abilities and possible mechanisms in young rats with kindling - induced epilepsy, and on the activity of acetylcholinesterase （ACHE） and choline acetyhransterase （CHAT） in rat. Methods 40 postnatal day 21 （P21） and 40 postnatal day 35 （P35） Spragne- Dawley （SD） rats were randomly assigned respectively into 5 groups： normal saline （NS） control, kindling epilepsy model, high, middle and low dosage of EGb -treated kindling epilepsy af- ter preliminary screening by Y - maze test. The kindling model was established by an intraperitoneal injection of pentet- razole （PTZ）. The variations of learning- memory ability and the activity of AChE and ChAT in the hippoeampus were observed by Y - maze test and biochemistry determination. Results EGb could obviously improve the achievement of Y -maze test of the kindling model in a dose -dependent manner, with the activity of AChE and ChAT in the hippocampus inhibited and increased, respectively. Conclusion EGb can improve learning - memory ability in epileptic rats of developmental phase by increasing the ChAT activity and reducing the AChE activity, which niay contribute to its action in improving the ability of cholinergic nervous system.