丰富环境干预对孕期手机辐射暴露后仔鼠认知功能的影响

目的:探讨丰富环境干预对孕期长时间手机辐射暴露后仔鼠认知功能的影响。方法:18只SPF级SD孕鼠随机分为两组,分别给予对照处理(不辐射)、长时间手机辐射处理(辐射24 h/d,21d),待仔鼠出生后饲养至18月龄,进行丰富环境干预,共分为3组,分别为对照组(CON)、手机辐射组(PR)及丰富环境组(PR+EE)。于丰富环境干预28 d后应用Morris水迷宫评定仔鼠认知功能;免疫组化及Western Blot检测海马区突触素(SYN)和脑源性神经营养因子(BDNF)表达;透射电镜观察海马区突触的超微结构。结果:与CON组相比,PR组及PR+EE组仔鼠的逃避潜伏期延长,跨越平台的次数减少,SYN和BDNF表达均减少,海马CA1区超微结构改变;而与PR组相比,PR+EE组逃避潜伏期缩短,穿越平台次数增加,SYN和BDNF表达均上调,且SYN阳性细胞增多,海马CA1区突触超微结构改变。结论:丰富环境干预可能通过上调海马SYN和BDNF表达,改变突触超微结构,提高突触可塑性,进而改善孕期手机辐射暴露后仔鼠的认知功能。

The effects of enriched environments on prenatal mobile phone exposure on cognitive function of rat offspring

Objective:To investigate the effects of enriched environment on long-term prenatal exposure to mobile phone on cognitive function in offspring rats.Methods:Eighteen specific pathogen free Sprague-Dawley pregnant rats were randomly divided into two groups:control treatment and prenatal mobile phone exposure treatment(radiation for twenty-four hours per day during all the pregnancy).Keeping all offspring rats randomly until eighteen months,enriched or standard environment intervention were conducted on offspring rats.The offspring rats were divided into three groups:the control group(CON),the pregnant radiation group(PR),the pregnant radiation and enriched environment group(PR+EE).Morris water maze was used to assessed rats’capability of cognitive function after enriched environment intervention.The expression of synaptophysin(SYN)and brain derived neurotrophic factor(BDNF)in hippocampus of offspring rats were detected by immunohistochemistry and Western Blot.The ultrastructure of the synaptic in hippocampus was observed by transmission electron microscope.Results:Compared with the CON group,escape latency significantly increased,the number of platform crossings significantly decreased in Morris water maze,and the expression of SYN and BDNF decreased within hippocampus in the PR group.Compared with the PR group,the rats in the PR+EE group showed the escape latency for searching the hidden platform obviously decreased and the number of platform crossings increased.Moreover,SYN positive cells and the expression of SYN and BDNF in hippocampus of offspring rats significantly increased and the hippocampus CA1 region ultrastructure of the synaptic changed.Conclusion:Enriched environment might influence cognitive function by improving the expression of SYN and BDNF and changing the synaptic structure of hippocampus and regulating synaptic plasticity.