急性最大电休克和慢性经耳电点燃癫痫对大鼠学习和记忆的影响  

Effects of acute maximal electroshock and chronic transauricular kindled seizures on learning abilities in Sprague-Dawley rats

作　　者：李青[1] 吴登唱[1] 张琦[2] 陈忠[1] 

机构地区：[1]浙江大学医学院药理学教研室,浙江杭州310058 [2]浙江医学高等专科学校生理学教研室,浙江杭州310053

出　　处：《浙江大学学报（医学版）》2007年第2期134-140,共7页Journal of Zhejiang University(Medical Sciences)

基　　金：国家自然科学基金资助项目(30371638);浙江省青年人才基金项目(R303779);浙江医学高等专科学校自然科学基金项目(2005XZ03)

摘　　要：目的:探讨急性最大电休克和慢性经耳电点燃癫痫对大鼠学习和记忆的影响。方法:通过双耳夹给予大鼠电刺激(150mA,0.2s)诱发急性最大电休克(MES),而慢性经耳电点燃癫痫,是经双耳夹每24h给予大鼠一次亚惊厥剂量电刺激(40mA,0.2s)直至完全点燃。采用八臂迷宫(四臂放饵)研究大鼠空间学习能力和记忆再现能力。高效液相色谱分析法(HPLC)检测脑中组胺、γ-氨基丁酸(GABA)、谷氨酸的含量变化。结果:在学习过程中,与对照组相比,急性最大电休克仅增加了学习过程中的参考记忆错误次数,同时使大鼠海马内GABA含量增加。而慢性经耳电点燃癫痫在空间记忆再现过程中,大鼠工作记忆和参考记忆错误次数增加并且在完全点燃后持续近3周。慢性经耳电点燃癫痫大鼠在完全点燃24h后海马CA1区神经元发生退行性变化,同时使大鼠海马组胺含量减少。结论:不同种癫痫对认知功能的影响不同:(1)急性最大电休克损伤了空间学习能力,可能与异常的突触可塑性及海马内的GABA含量上升有关;(2)慢性经耳电点燃癫痫诱发了空间记忆再现障碍,可能与海马CA1区神经元的病理改变及海马内组胺含量的下降有关。Objective： To investigate effects of acute maximal electroshock （MES） and chronic transauricular kindled seizures on learning abilities in Sprague-Dawley rats. Methods： An acute MES was induced by giving an alternating current （150 mA, 0. 2 s） through ear-clip electrodes. Chronic transauricular kindled seizure was induced by repeated application of initially subconvulsive electrical stimulation （40 mA,0. 2 s） through ear-clip electrodes once every 24 h.An 8-arm radial maze （4 arms baited） was used to measure learning abilities. Histamine, glutamate and γ-aminobutyric acid （GABA） were measured by high-performance liquid chromatography （HPLC）. Results： In the acquisition learning process,an acute MES increased reference memory errors but not working memory errors. In addition,it increased GABA levels in the hippocampus. On the other hand, chronic transauricular kindled seizures increased both working and reference memory errors in retrieval memory process,and this lasted for at least 3 weeks. Chronic transauricular kindled seizures induced CA1 neuron damage and a decrease in histamine levels in the hippocampus. Conclusion： Different types of kindling seizure produce different effects on cognitive behavior： （1） an acute MES impairs learning ability,which may be associated with an abnormal plasticity and an increase of GABA in the hippocampus; （2） the chronic transauricular kindled seizure impairs retrieval memory mainly,which may be related to CA1 neuron damage and a decrease in histaminergic activity in the hippocampus.

关 键 词：癫痫/病理生理学 记忆障碍/病因学 参考记忆 工作记忆 动物 实验 

分 类 号：R742.1[医药卫生—神经病学与精神病学]