血管性痴呆大鼠海马突触结构参数的变化

目的 :观察血管性痴呆大鼠海马突触结构特点 ,探讨血管性痴呆学习记忆障碍的神经病理机制。方法 :采用永久性结扎双侧颈总动脉的方法建立血管性痴呆动物模型 ,利用Morris水迷宫和Y型电迷宫检验大鼠的学习记忆能力 ,应用透射电镜和形态计量学分析血管性痴呆大鼠海马GrayⅠ型突触的突触结构参数的变化。结果 :血管性痴呆大鼠海马CA1区GrayⅠ型突触的体积密度、面积密度、比表面和面数密度均减小 ,突触平均面积增大 ;突触界面曲率、突触间隙宽度、突触后致密物厚度均减小。结论 :永久性结扎双侧颈总动脉使大鼠海马CA1区GrayⅠ型突触数量减少和形态结构发生显著变化 ,导致学习记忆障碍

Changes of the hippocampal synaptic structural parameters in vascular dementic rats

Objective:To observe the character of hippocampal synaptic structure and to study the nervous mechanism of hypomnesia in vascular dementia.Methods:Permanent occlusion of bilateral common carotid arteries of rats was used to establish the animal vascular dementic models.Rats were tested by Y type maze and Morris water maze.The changes of the hippocampal synaptic structural parameters were studied with electron microscope and morphometric analysis.Results:The volume density,surface density,specific surface and numerical density on area of Gray type I synapses in CA 1 sector of hippocampus in vascular dementic rats were decreased significantly.However,the mean profile area of synapse was increased.Moreover,the curvature of synaptic interface,the width of synaptic cleft and the thickness of postsynaptic density were decreased.Conclusion:The hypomnesia is from changes of synaptic structure and synaptic number following permanent occlusion of bilateral common carotid arteries in rats.