摘要
目的观察幼年应激对成年大鼠应激敏感性的影响及神经机制。方法将60只雄性SD大鼠随机分为应激组（30只）和非应激组（30）只，应激方式为强迫游泳。应激前及应激结束8周后两次以提尾实验评定大鼠的情绪性行为以观察大鼠的应激敏感性。行为评定完毕后光镜下观察左侧海马CA3区锥体细胞数目，电镜下拍摄左侧海马CA3区突触照片，然后在全自动图像分析仪下分析突触的形态学变化。结果（1）应激前后应激组大鼠情绪性行为得分增加数[（1．20±0．60）分]大于非应激组[（-0．13±0．83）分]（P〈0．05）。（2）应激组大鼠左侧海马CA3区锥体细胞数[（36．34±1．23）个]小于非应激组大鼠[（42．24±1．48）个]（P〈0．05）。（3）应激组大鼠左侧海马CA3区突触数密度[（1．01±0．15）N／μm^3]、面密度[（0．20±0．04）μm^2／μm^3]、圆盘面积[（0．05±0．02）μm^3]、活性区长度：（314．78±46．32）nm]、曲率（1．02±0．04）、突触后致密物质厚度[（46．35±6．81）nm]小于非应激组数密度[（1．16±0．21）N／μm^3]、面密度[（0．29±0．06）μm^2／μm^3]、圆盘面积[（0．07±0．02）μm^2]、活性区长度：（339．83±55．16）nm]、曲率（1．11±0．06）、突触后致密物质厚度[（71．32±9．55）nm]。结论幼年应激会增加成年大鼠的应激敏感性；神经可塑性的降低可能是其机制。
Objective To observe the influence of stress in childhood on adult rat＇s stress sensitization and the neural mechanism. Methods Sixty male Sprague-Dawley rats were randomly divided into stress group （thirty） and non-stress group（ thirty）. The rats in stress group were given 14 repeated daily forced swimming, The emotional behaviors were tested at the beginning of the experiment and when stress of forced swimming ended 8 weeks later. When the appraisal of behavior ended, the pyramidal neuron in the left hippoeampal CA3 regions were counted under the light microscope, the pictures of synapses in the left hippoeampal CA3 regions were got under the eleetromieroscope,and the morphological changes of synapses were analyzed with the automatic image analyzing system. Results （ 1 ） The score （ 1.20±0.60） of emotional behavior of stress group increased more than non- stress group（-0.13±0.83） （P 〈0.05） . （2） The number of pyramidal neuron in the left hippocampal CA3 regions of stress group rats was small than that of non-stress group rats. （ 3 ） The number density [（ 1.01±0.15 ） N/μm^3] , prosop density （ 0.20±0.04 ） μm^2/μm^3 ] , the average area of synaptie linkage [（0.05±0. 02 ）μm^2] , the length of active areas [（314.78±46.32 ）nm], the curvatures （1.02±0.04） , the thickness of postsynaptic dense material [（46.35±6.81）nm] in the left hippocampal CA3 regions of the stress group were small than those of non-stress group （P 〈 0.05）. Conclusion The stress in childhood could increase the stress sensitization of adult rats,and the decrease of synaptic plasticity might be the mechanism.
出处
《中华行为医学与脑科学杂志》
CAS
CSCD
北大核心
2009年第8期682-684,共3页
Chinese Journal of Behavioral Medicine and Brain Science
基金
广东省重点科技攻关项目（2KM05701S）
关键词
强迫游泳
应激敏感性
突触
锥体细胞
大鼠
Forced swimming test
Stress sensitization
Synapse
Pyramidal neuron
Rats
