中国临床心理学杂志

慢性应激导致大鼠颅脑损伤的磁共振研究

作者：王曼¹ 谢守付² 金魁和¹

单位：1. 中国医科大学第一医院精神医学科辽宁沈阳 110001
2. 大连市第七人民医院辽宁大连 116023

关键词：应激海马凋亡磁共振

分类号：R741;R445.2

出版年,卷(期):页码：2010,18(3):278-280

摘要：

目的：探讨慢性应激时大鼠中枢神经元损伤与大脑结构、功能改变之间的关系。方法：30只青年雄性Wistar大鼠，体重在185g~255g之间，随机分为对照组(C组，n=15)和实验组(T组，n=15)。T组大鼠单只分笼喂养，连续21天给予不可预见性综合刺激：C组大鼠分5只/笼喂养，不给予任何刺激。第22天脑组织取材、切片并进行TUNEL染色测定：实验前后分别进行旷场分析、体重测定和头部磁共振检查。结果：实验后的T组与C组相比：体重减轻(P<0.05)：中央格停留时间延长(P<0.01)：水平穿越格数减少(P<0.01)：直立次数减少(P<0.01)：修饰次数减少(P<0.01)：粪便粒数增多(P<0.01)。在T组及C组海马各区均可以观察到细胞核内有棕黄色颗粒的凋亡细胞。慢性应激后T组与C组比较，凋亡细胞所占比例及凋亡细胞计数明显增加，两组有显著性差异(P<0.01)。无论与C组还是与实验前本组相比，实验后T组大鼠的侧脑室宽度显著增大，中脑导直径显著增大(P值均<0.01)。结论：慢性不可预见性综合应激明显增加了大鼠海马各亚区神经元凋亡的数量，并使其头部的MR图像表现为脑萎缩。

Objective:To study the relationship between the damage of the central neuron and the brain structure and function of the rats with chronic stress.Methods:Male Wistar rats(n=30) weighting about 185-255g were divided into the test group(T,n=15) and the contral group(C,n=15) randomly.The rats in group T were exposed to various types of stresses every day for consecutive 21 days.The rats in group C did not receive any stress during 21 days.Every rat was weighed,open-field tested and measured for the brain by MR before the test and on the 22nd day.Also,on the 22nd day,the brains were removed and cut coronally.The apoptosis was detected by techniques of terminal deoxynucleotibyl transferase(TdT)-mediated dUTP nick end labling(TUNEL).Results:Weight and the result of Open-field test: compared with group C,group T showed less weight,increased stopping time in the center,decreasing rearing and grooming and increased defecation after 21-day stress(P<0.01-0.05).Compared with group C,the percentage of positive cells in the hippocampus of group T increased significantly in the TUNEL method(P<0.01).Compared with group C or before experiment,the lateral cerebral ventricle width and the diameter of midbrain aqueduct in group T increased after 21-day stress(P<0.01).Conclusion:After the chronic stress,the apoptosis of the neurons in the rats hippocampus were increases and the MR image of brain shows cerebral atrophy.

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参考文献：

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