慢性应激大鼠海马CA3区锥体细胞树突超微结构的改变  

Ultrastructural changes of dendrites of pyramidal neurons in hippocampal CA3 region of rats with chronic stress

作　　者：金海燕[1] 刘少文[2] 杨权[2] 张丽红 

机构地区：[1]广东省人民医院精神卫生研究所,广东省广州市510180 [2]汕头大学精神卫生中心,广东省汕头市515041 [3]辽宁省中医学院基础医学院,辽宁省沈阳市110032

出　　处：《中国临床康复》2005年第5期76-77,共2页Chinese Journal of Clinical Rehabilitation

摘　　要：目的:观察慢性应激大鼠海马CA3区锥体细胞树突超微结构特别是微管形态的改变,探讨慢性应激后产生的学习记忆及情绪障碍的可能机制。方法:实验于2003-01在汕头大学医学院进行。取健康清洁级雄性SD大鼠30只,随机分为对照组15只,应激组15只。应激组完成强迫游泳4周,对照组在笼中饲养4周后,测定两组大鼠海马CA3区锥体细胞一级树突的长度及直径,观察海马CA3区锥体细胞树突的超微结构。结果:慢性应激大鼠海马CA3区锥体细胞树突纵切面微管断裂,平行微管间距离变宽;横切面微管环不完整,单体分布不均匀;线粒体嵴模糊,偶可见空泡样变性。应激组大鼠海马CA3区锥体细胞一级树突的长度及直径分别为(98.51±17.48),(6.41±0.94)μm,对照组为(125.35±18.69),(5.67±0.83)μm,两组比较差异有显著性意义(P<0.05)。结论:慢性应激可导致大鼠海马CA3区锥体细胞树突骨架尤其是微管的损害,并直接导致一级树突变短、变粗。AIM:To observe the changes of the dendritic ultrastructure,especially the morphology of microtubule,in the hippocampal CA3 pyramidal neurons of rats with chronic stress,and investigate the possible mechanism of learning and memory disorder and emotional disorder after chronic stress. METHODS:The experiment was completed in the Medical College of Shantou University in January 2003.Thirty healthy male SD rats of clean degree were randomly divided into control group(n=15) and stress group(n=15).Rats in the stress group were subjected to forced swimming for 20 minutes a day for four weeks,while those in the control group were fed in the cages for four weeks,and then the diameter and length of first degree dendrite in hippocampal CA3 pyramidal neurons were measured,and the ultrastructure of dendrite in rat hippocampal CA3 pyramidal neurons was observed in both groups. RESULTS:The following ultrastructural changes of dendrites were observed in the hippocampal CA3 pyramidal neurons of rats in the stress group:fragmentation of microtubule,widening of spacing between parallel microtubules in longitudinal section,irregularity of annular and maldistribution of monome in cross section,crista clouding or degeneration as vacuoles of mitochondrion.The length and diameter of dendrite in the hippocampal CA3 pyramidal neurons of rats in the stress group[(98.51±17.48),(6.41±0.94) μm] were significantly different from those in the control group[(125.35±18.69),(5.67±0.83) μm](P< 0.05). CONCLUSION:Chronic stress can result in the damage of dendritic shaft,especially the damage of microtubules,and then lead to the shortening and thichness of first degree dendrite in the hippocampal CA3 pyramidal neurons of rats.

关 键 词：应激 海马 锥体细胞 树突 

分 类 号：R74[医药卫生—神经病学与精神病学]