学习状态对齿状回神经干细胞增殖的影响

Effect of effort of learning on the proliferation of neural stem cells in dentate gyrus

目的:观察学习状态与学习不良对齿状回神经干细胞增殖状况的影响。方法:本实验于2005-5/10在广西医科大学神经解剖实验室完成,实验动物为成年雄性昆明小鼠,共27只,动物随机分为水迷宫训练组(n=18)及对照组(n=9)。对照组不进行水迷宫训练,水迷宫训练组在经过训练后,根据其水迷宫训练中的表现将动物分为正常学习组和不良学习组。水迷宫训练组动物于水迷宫训练最后3d,以40mg/kg进行5-溴脱氧尿苷(BrdU)腹腔注射,每日3次,12h内完成。对照组同步进行5-溴脱氧尿苷注射;然后在水迷宫训练后的第1、7、14天,应用免疫组化染色检测齿状回神经干细胞的增殖及存活情况。结果:各组实验动物均进入结果分析,无脱落。①学习状态对神经干细胞增殖的影响:正常学习组小鼠的5-溴脱氧尿苷阳性细胞数明显多于对照组和不良学习组(P<0.01),而对照组与不良学习组之间差异无显著性(P>0.05)。②学习状态对增殖神经干细胞细胞存活的影响:水迷宫训练后第7天,正常学习组与不良学习组小鼠齿状回5-溴脱氧尿苷阳性细胞均数均明显多于对照组(P<0.01),正常学习组5-溴脱氧尿苷阳性细胞数多于不良学习组(P<0.05);水迷宫训练后第14天,正常学习组与不良学习组小鼠齿状回5-溴脱氧尿苷阳性细胞均数仍明显多于对照组小鼠(P<0.01);而正常学习组与不良学习组之间差异无显著性。结论:神经干细胞的增殖活动不但受到学习记忆的调节,而且还与学习状态有关,但不良学习状态对齿状回的神经干细胞增殖不产生影响。

AIM： To observe the effect of learning effort and poor learning and memory on the proliferation of neural stem cells in dentate gyms METHODS： This experiment was conducted at the laboratory of Nerve Anatomy, Guangxi Medical University from May to October 2005. Totally 27 adult male Kunming mice were used in this experiment ,and they were randomly divided into water maze training group （n=lg）and control group（n=9）, No water maze training was given in the control group. After training, mice in the water maze training group were divided into normal learning group and poor learning group according to the behavior of the mice in the water maze training . At the final three days of the maze training, animals of the Water maze training group received three injection of 5-bromodeoxyuridine （5-BrdU） （50mg/kg i.p, three times within 12 hours） per day. 5-BrdU was also given in the control group within the same daytime period as water maze training group. The proliferation and survival of neural stem cells were detected with immunohistochemical staining at 1, 7 and 14 days after training. RESULTS： All the animals entered the stage of result analysis with no loss in the midway. ①Effect of effort of learning on the proliferation of neural stem cells： The number of BrdU-labeled cells in the dentate gyms of the mice was much more in the normal learning group than in the control group and poor learning group （P〈0.01）,while there was no significant difference between control group and poor learning group （P〉0.05）.② Effect of effort of learning on the survival of pew cells： At 7 days after water maze training, the number of BrdU-labeled cells in dentate gyrus was significantly more in the normal learning group and poor learning group than in the control group （P〈0.01）,and the number of BrdU-labeled cells in dentate gyms was more in the normal learning group than in the poor learning group （P〈0.05）;At 14 days after water maze training, the number of BrdU-labeled cells was still more in the normal learning group and poor learning group than in the control group （P〈0.01 ） ;There was no significant difference between normal learning group and poor learning group. CONCLUSION： The proliferation of neural stem cells is not only regulated by learning and memory, but also related to the effect of learning. But, poor effect of learning does not affect the proliferation of neural stemcells in the dentate gyms.