微波辐射对大鼠海马结构和功能的影响及突触素Ⅰ在其中的作用  

Effect of microwave radiation on hippocampal structure and function in Wistar rats and its relationship with synapsin Ⅰ

作　　者：乔思默[1] 胡向军[1] 王丽峰[1] 彭瑞云[1] 高亚兵[1] 王水明[1] 赵黎[1] 徐新萍[1] 董霁[1] 常公民[1] 苏镇涛[1] 

机构地区：[1]军事医学科学院放射与辐射医学研究所,北京100850

出　　处：《军事医学》2013年第2期126-129,140,共5页Military Medical Sciences

基　　金：国家自然科学基金青年科学基金资助项目(30900382)

摘　　要：目的探讨微波辐射对大鼠空间学习记忆功能、海马组织结构、苔藓纤维出芽及其与突触素Ⅰ表达的影响。方法实验选用雄性Wistar大鼠,随机分为假辐射组及辐射组,采用30 mW/cm2微波辐射Wistar大鼠,于辐射后6 h、1 d、2 d、3 d、4 d、7 d、14 d以Morris水迷宫对辐照后大鼠空间学习记忆功能改变进行观察;于辐射后6 h、1 d、3 d、7 d、14 d、28 d采用HE染色和免疫荧光对大鼠海马组织结构和突触素Ⅰ表达进行观察;于辐射后7 d、14 d、28 d进行Timm染色,对学习记忆后大鼠海马苔藓纤维出芽情况进行观察。结果 30 mW/cm2微波辐射可引起大鼠海马齿状回颗粒细胞和CA3区锥体细胞损伤,锥体细胞层和颗粒细胞层部分锥体细胞及颗粒细胞固缩深染,部分胶质细胞固缩、深染,血管周围间隙增宽,辐照后6 h～7 d,30 mW/cm2组损伤程度呈逐渐加重趋势,辐射后14 d,30m W/cm2组损伤呈恢复趋势;辐射后6 h、1 d、2 d、7 d,30 mW/cm2组Morris水迷宫平均逃避潜伏期,较假辐射组明显延长(P<0.01或P<0.05);Timm染色结果显示,辐射后即水迷宫后7 d、14 d和28 d,30 mW/cm2组海马苔藓纤维出芽,与假辐射组比较,苔藓纤维出芽明显减少(P<0.01或P<0.05)。免疫荧光结果显示,微波辐射后3 d,海马CA3区及齿状回突触素Ⅰ表达明显减少,且其表达减少的部位和时间与海马神经元损伤以及苔藓纤维出芽受抑制的部位和时间一致。结论微波辐射可能通过抑制海马突触素Ⅰ的表达,导致突触结构损伤(表现为苔藓纤维出芽生长抑制),最终导致学习和记忆能力下降。Objective To investigate the effect of microwave radiation on the hippocampal structure, the ability of learning and memory, the mossy fiber sprouting and expression of synapsin I in rats. Methods Faty Wistar rats were exposed to microwave at an average power density 30mW/em2. The ability of learning and memory was detected by Morris water maze at 6 h, 1 d, 3 d, 7 d and 14 d after exposure. The hippocampal structure and the expression of synapsin I were observed by HE staining and immunofluoresence at 6 h, 1 d, 3 d, 7 d, 14 d and 28 d after exposure. The mossy fiber sprouting was detected by Timm staining at 7 d, 14 d and 28 d after exposure. Results The average escape lateneies of 30 mW/cm2 group were longer than those of sham group （P 〈0.01 or P 〈0.05） at 6 h, 1 d, 2 d, 7 d after exposure by the Morris water maze. Microwave radiation of 30 mW/em2 induced the injury to the hippocampal structure. Pycnosis and deep staining of pyramidal cells, granular cells and glial cells were observed in the pyramidal layer and granular cell layer in the CA3 and the dentate gyrus of the hippocampus. Vascular enlarged perivascular spaces were detected in the same location of the hippocampus. The mossy fiber sprouting of 30 mW/cm2 group was decreased compared to sham group （ P 〈0.01 or P 〈0.05） at 7 d, 14 d, 28 d after exposure. At 3 d after exposure, the synapsin I expression was significantly downregulated in the CA3 and the dentate gyms of the hippocampus which was consistant with the inhibition of mossy fiber sprouting by its time and location. Conclusion Microwave radiation can induce the damage to the ability of learning and memory, injury to hippocampal structure and inhibition of mossy fiber sprouting by downregulating the expression of synap- sin I in rats.

关 键 词：微波 海马 MORRIS水迷宫 学习记忆 苔藓纤维 突触素I 

分 类 号：R363[医药卫生—病理学]