断乳前丰富环境对大鼠空间参考记忆及海马CA1区神经元形态学的影响  

Effects of preweaning enriched environment on spatial memory and morphological changes of hippocampal CA1 neurons of the rats

作　　者：陆澄秋[1] 钟乐[1] 颜崇淮[1] 田英[1] 沈晓明[1] 

机构地区：[1]上海交通大学医学院附属新华医院上海市儿科医学研究所上海市环境与儿童健康重点实验室,上海200092

出　　处：《中国儿童保健杂志》2008年第4期428-429,432,共3页Chinese Journal of Child Health Care

基　　金：上海市重点实验室(06DZ22024);上海市儿科学重点学科(T0204);上海市医学重点学科(05Ⅲ002)资助项目;上海市科委重大基础研究项目基金资助(05DJ14007)

摘　　要：【目的】探讨断乳前丰富环境对大鼠空间参考记忆和海马CA1区锥体神经元树突结构可塑性的影响。【方法】3窝共30只新生SD大鼠,每窝均随机分为对照组(n=14)和实验组(n=16)。实验组大鼠生后10日龄至24日龄每天予以丰富环境暴露20 min,对照组大鼠除不予以丰富环境暴露外,余处理均与实验组相同。生后5周,两组大鼠予以Morris水迷宫测试评估空间参考学习记忆能力。同时,采用高尔基染色法观察断乳前丰富环境对大鼠海马CA1区锥体神经元树突形态的影响,并进行统计分析。【结果】在Morris水迷宫测试中,丰富环境组大鼠的空间参考记忆成绩显著高于对照组。在训练阶段,两组到达平台的平均时间均呈下降趋势。在测试阶段,丰富环境组大鼠的空间记忆保持能力优于对照组[(31.41±5.91)%vs(26.17±5.66)%,F=4.470,P<0.05)。高尔基染色显示断乳前丰富环境增加海马CA1区锥体神经元顶树突和基树突的长度[(3.46±0.65)mm vs(2.48±0.57)mm;(2.30±0.48)mm vs(1.93±0.53)mm;F=29.838,P<0.01;F=6.222;P<0.05]。【结论】断乳前丰富环境可以促进大鼠空间参考记忆能力,增加海马CA1区锥体神经元顶树突和基树突的长度。[Objective] To explore the effects of preweaning enriched environment on spatial memory and the mor phological changes of the hippocampal CA1 neurons of rats. [Method] Three dams, totally thirty newborn rats were in volved in this experiment. Each dam was randomly assigned into control group （n=14） and experimental group （n =16）. The exposure of enriched environment lasts two weeks until weaning. Morris water maze test was performed at postnatal day 35. The morphological changes of hippocampal CA1 neurons were detected by Golgi staining. [Results] Both the two groups showed a decreased escape latency in the training section of Morris water maze test. In test section, the enriched rats also showed a better performance. The time percent of their staying in the target quadrant was significant longer than the control group [（31.41±5.91）% vs （26.17±5.66）% ,F=4. 470,P〈0.05）]. A Golgi staining morphological analysis of neuronal changes in hippocampal CA1 neurons showed that the total length of the apical and basal dendrites was longer than the control rats[（3.46±0.65）mmvs （2.48±0.57）mm; （2.30±0.48）mmvs（1.93±0.53） mm;F =29. 838, P〈0.01 ;F =6. 222 ;P〈0.05]. [Conclusion] Preweaning enriched environment can promote spatial memory and increa ses length of the dendrites of hippocampal CA1 neurons of the rats.

关 键 词：丰富环境 树突 海马 空间记忆 断乳前 

分 类 号：R722.12[医药卫生—儿科] R743.31[医药卫生—临床医学]