游泳训练对三甲基氯化锡致记忆障碍模型小鼠学习记忆的影响

Effects of Swimming Training on Learning and Memory Impairment Induced by Trimethyltin Chloride in BALB/c Mice

目的探讨游泳训练对三甲基氯化锡（TMT）致记忆障碍模型小鼠学习记忆能力的影响及其机制。方法 6~9周龄BALB/c小鼠随机分为生理盐水对照组、TMT组、（生理盐水＋训练）组、（TMT＋训练）组（前两组各20只,后两组各10只）,均腹腔注射给药;前两组不做游泳训练,后两组自给药24 h后,连续进行游泳训练7 d;用Morris水迷宫检测给药后24 h及第8 d小鼠学习记忆能力,采用Western blot法检测给药后24 h及第8 d小鼠海马脑区生长相关蛋白（GAP-43）、突触囊泡蛋白（SYP）。结果给药后24 h及第8 d,与生理盐水组相比,TMT组小鼠逃逸潜伏期明显延长（P〈0.05）;给药后第8d,与生理盐水组及（生理盐水＋训练）组相比,（TMT＋训练）组小鼠逃逸潜伏期差异无统计学意义（P〉0.05）;给药后24 h,与生理盐水组相比,TMT组海马脑区SYP表达降低（P〈0.05）,GAP-43表达差异无统计意义（P〉0.05）;给药后第8 d,与TMT组相比,（TMT＋训练）组海马脑区GAP-43和SYP表达增加（P〈0.05）;与（生理盐水＋训练）组相比,（TMT＋训练）组海马脑区GAP-43、SYP表达差异均无统计学意义（P〉0.05）。结论游泳训练有改善TMT致记忆障碍模型小鼠学习记忆能力的作用,其机制可能与海马脑区GAP-43和SYP表达增加有关。

Objectives To explore the effects and mechanism of swimming training on learning and memory impairment induced by trimethyltin chloride（ TMT） in BALB /c mice. Methods 6 - 9 week-old BALB /c mice were randomly divided into 4 groups： saline group,TMT group,saline ＋ swimming training group（ saline ＋ ST）,and TMT ＋ swimming training group（ TMT ＋ ST）. There were 20 rats each in saline group and TMT group and 10 rats each in the other two groups. Equal volume of normal saline solution or TMT（ 2. 25 mg /kg·BW） in normal saline solution were injected intraperitonealy after an adaptation to the laboratory for one week. Swimming training was conducted daily for 7 days started from 24 h after the injection of TMT or saline. Morris water maze（ latency escape） for testing the learning and memory ability,and western blot for analyzing growth associated protein（ GAP- 43） and synaptophysin（ SYP） in the hippocampus of mice were conducted at 24 h and in the 8th day after the injection of TMT or saline. Results Comparing with the saline group,the latency escape was significantly prolonged（ P 〈 0. 05） in TMT group at 24 h and in the 8 th day after the administration of TMT. Comparing with the saline group and saline ＋ ST group,the latency escape in TMT ＋ ST group was not significantly different（ P 〉 0. 05） after the injection of TMT for 7 days. Comparing with the saline group,the expression of SYP decreased（ P 〈 0. 05）in hippocampus in the TMT group after injection for 24 h,and the expression of GAP- 43 in hippocampus in TMT group showed no statistical significance（ P 〉 0. 05）. Comparing with the TMT group,the expression of GAP- 43 and SYP in the hippocampus of TMT ＋ ST group increased（ P 〈 0. 05） after the injection of TMT for 7 days; while comparing with the saline group and saline ＋ ST group,the expression of GAP- 43 and SYP in hippocampus in TMT ＋ ST group was not statistically different（ P 〉 0. 05）. Conclusions The learning and memory ability of mice impaired by TMT could be improved by swimming training,and its potential mechanism might be related to the increased expression of SYP and GAP- 43 in hippocampus.