丰富环境对缺血性脑卒中小鼠海马区Bcl-2和Bax蛋白表达和认知功能的效果

Effects of Enriched Environment on Cognition and Expression of Bcl-2/Bax Protein in Hippocampus after Ischemic Stroke in Mice

目的探讨丰富环境干预对缺血性脑卒中小鼠空间学习记忆能力,以及海马区凋亡相关蛋白Bcl-2和Bax表达的影响。方法清洁级成年雄性C57BL/6小鼠42只,接受永久性左侧大脑中动脉栓塞术。术后3 d,将造模成功的小鼠32只随机分为标准饲养组(n=16)和丰富环境组(n=16)。另选8只小鼠为假手术组。假手术组和标准饲养组置于标准环境中饲养,丰富环境组置于丰富环境中饲养。21 d后,行Morris水迷宫测试,Western blotting和免疫荧光染色检测海马区Bcl-2和Bax蛋白水平。结果与标准饲养组相比,丰富环境组逃避潜伏期缩短(P<0.05),目标象限内停留时间、停留距离和穿过原有平台次数增加(P<0.05);Bcl-2水平升高(P<0.05),Bax水平降低(P<0.05)。结论丰富环境可以改善缺血性脑卒中小鼠空间学习和记忆功能,可能与抵制海马区细胞凋亡有关。

Objective To explore the effect of enriched environment on spatial learning and memory of mice after ischemic stroke and the expression of apoptotic regulatory protein Bcl-2 and Bax in hippocampus.Methods Clean grade adult male C57BL/6 mice(n=42)were occluded left middle cerebral artery permanently.Three days after operation,the modeling mice were randomly divided into standard group(n=16)and enriched environment group(n=16).Other eight mice were as sham group.The sham group and the standard group were fed in standard environment,while the enriched group was fed in enriched environment.They were tested with Morris Water Maze 21 days after intervention,and the expression of Bcl-2 and Bax protein in hippocampus was detected with Western blotting and immunofluorescence staining.Results The latency was less in the enriched group than in the standard group(P<0.05),and the time and swimming distance staying in the target quadrant were more(P<0.05),as well as the times crossing the target quadrant(P<0.05).Compared with the standard group,the expression of Bcl-2 increased in the enriched group,while the expression of Bax decreased(P<0.05).Conclusion Enriched environment can improve the spatial learning and memory of mice after ischemic stroke,which may be associated with reducing apoptosis in hippocampus.