尼莫地平对癫痫大鼠学习记忆及海马超微结构的影响

目的探讨尼莫地平(nimodipin,NIM)对戊四氮(pentylenetetrazol,PTZ)点燃癫痫大鼠学习记忆能力及海马CA3区超微结构的影响。方法动物分为正常对照组、PTZ组和NIM PTZ组,采用PTZ慢性点燃癫痫模型,应用Morris水迷宫观察各组大鼠空间学习记忆能力,电镜观察海马CA3区突触界面结构,并对突触活性参数量化分析。结果PTZ点燃癫痫大鼠存在学习记忆能力下降,其海马CA3区突触后致密物显著变薄、突触小泡显著减少、突触间隙显著增宽(P<0.05);尼莫地平能改善癫痫大鼠学习记忆障碍,与PTZ组比较,突触后致密物增厚、突触小泡增多、突触间隙变窄(P<0.05)。结论PTZ点燃癫痫大鼠存在空间学习记忆受损,可能与突触界面参数改变有关;NIM可以改善癫痫大鼠突触超微结构,提高学习记忆能力。

Effect of nimodipin on spatial learning and memory and ultrastructural changes in hippocampus of epileptic rats

Objective To explore the effect of nimodipin(NIM) on spatial learning and memory and ultrastructural changes in CA3 region of rats with chronic epilepsy induced by pentylenetetrazol(PTZ).Methods Rats were divided into normal control group,PTZ group and NIM PTZ group.All of their behaviors were observed by Morris water maze.Meanwhile,ultrastructural observations on synapses in CA3 region were performed by electromicroscope,as well as quantitative analysis on their active parameters.Results The learning and memory ability of the epileptic rats was impaired,the thickness of postsynaptic density(PSD) and synaptic vesicles density(SVD) decreased significantly(P<0.05),the width of synaptic cleft(WSC) increased more markedly in PTZ group than in normal control group(P<0.05).Compared with PTZ group,the learning and memory ability of the NIM PTZ group rats was improved,the PSD and SVD increased(P<0.05),and the WSC decreased more markedly(P<0.05).Conclusion The impairment of learning and memory ability of the epileptic rats kindled by PTZ might be related with the changes of synaptic interface parameters.NIM can improve the learning and memory ability and change the synaptic interface parameters of epileptic rats.