丰富环境对老龄大鼠学习记忆功能与海马齿状回神经发生及DNA甲基化水平的影响  

The effects of enriched environments on neurogenesis and level of DNA methylation

作　　者：赵珊珊[1] 戚其学[2] 翟志永[1] 赵传胜[1] 

机构地区：[1]中国医科大学附属第一医院神经内科,辽宁沈阳110001 [2]中国医科大学附属第一医院血液流变室,辽宁沈阳110001

出　　处：《中国老年学杂志》2008年第18期1801-1803,共3页Chinese Journal of Gerontology

基　　金：国家自然科学基金青年基金面上基金资助项目(30500611);教育部留学回国人员科研启动基金资助项目(教外司留〔2006〕331号)

摘　　要：目的探讨丰富环境对老龄大鼠的学习记忆功能与海马齿状回神经发生的影响以及DNA甲基化在这个过程中的调控作用。方法将月龄为18个月的雄性Wistar大鼠随机分为丰富环境组和对照组,分别对两组进行水迷宫试验测试,标记、检测海马齿状回的神经干细胞并测定脑组织的5-甲基脱氧胞苷含量。结果丰富环境组大鼠的海马齿状回5-溴脱氧尿核苷(BrdU)阳性细胞数目〔(650±87)个/mm2〕显著高于对照组〔(420±58)个/mm2〕(P<0.05)。丰富环境组大鼠海马组织的5-甲基脱氧胞苷含量(5.4%±0.25%)明显高于对照组(4.2%±0.36%)(P<0.05)。与对照组相比,丰富环境组大鼠到达平台所需的时间明显缩短(P<0.05)。结论DNA甲基化可能参与了丰富环境促进老龄大鼠学习记忆功能与海马齿状回神经发生的调控。Objective To investigate the effects of enriched environments on the spatial learning and dentate neurogenesis of aged rats, and potential mechanisms of DNA methylation involved in this process. Methods Aged male Wistar rats （ 18 months old） were ran- domly divided into control and enriched environments groups, Spatial learning was evaluated by Morris water-maze test and the level of DNA methylation was measured by the amounts of 5-methyldeoxycytidine in hippocampus. Dentate neurogenesis was evaluated by the Brdu immu- nostainning. Results There was significant difference in the number of Brdu positive cells in dentate gyrus between enriched environments group [ （650 ±87）/mm^2] and control group [ （420 ±58）/mm^2, P 〈0. 05]. There was also a significant difference in the amount of 5- methyldeoxycytidine in hippocampas between enriched environments group （ 5.4% ± 0. 25% ） and control group （ 4. 2%± 0. 36%, P 〈 0. 05 ）. In addition, compared with control group, enriched environments group had shorter escape latency to find the hidden platform in water-maze test （ P 〈 0.05 ）. Conclusions DNA methylation may involve in the process of enhanced neurogensis induced by enriched environments with aged rats.

关 键 词：老化大鼠 神经发生 丰富环境 DNA甲基化 

分 类 号：R749.16[医药卫生—神经病学与精神病学]