脉冲微波照射后小鼠脑内星形胶质细胞的延迟效应  

Delayed response of astrocytes in the central nervous system of mice after pulsed microwave exposure

作　　者：牛富生[1] 王德文[2] 祝西里[3] 解恒革[1] 王鲁宁[1] 

机构地区：[1]解放军总医院南三科,北京市100853 [2]解放军军事医学科学院放射医学研究所,北京市100850 [3]北京大学电子学系,北京市100871

出　　处：《中国临床康复》2004年第19期3768-3769,共2页Chinese Journal of Clinical Rehabilitation

基　　金：国家自然科学基金资助项目(30070275)~~

摘　　要：目的:一些流行病学研究显示,电磁场暴露和阿尔茨海默病(Alzheimerdisease,AD)发病有一定关系,通过动物实验验证EMF暴露可能对中枢神经系统有延迟效应。方法:2月龄Km小鼠随机分为照射组和假照射组,照射组接受20minEMF照射,平均功率密度8.1mW/cm2,全身平均电磁波能量吸收比值(SAR)为2.4W/kg。分别于照射后3d,照射后8个月,照射组和假照射对照组每组随机抽取5只动物,进行脑病理形态学观察,包括胶质原纤维酸性蛋白(glialfibrillaryacidicprotein,GFAP)免疫组化染色显示星形胶质细胞,图像分析定量研究。结果:辐照前直肠温度(36.40±0.25)℃与辐照后(36.50±0.40)℃相比差异无统计学意义(t=-0.8480,P=0.4032)。照后3d,照射组和对照组相比,脑内星形胶质细胞的数量和形态没有明显变化。照后8个月,照射组小鼠海马星形胶质细胞较对照组增多(P<0.01),胶质细胞卫星化现象增多。胼胝体和杏仁核区皮质除了数量增多外,星形胶质细胞形态变化明显,表现在胞体增大,突起延长、增粗;胼胝体微血管周GFAP阳性染色加深;杏仁核区皮质星形胶质细胞成群聚集现象增多,且成群聚集的胶质细胞的突起向心化明显,认为这种现象是老年斑在形成。结论:微波照射造成了脑内延迟性损伤,或者加速了脑的老化。AIM:Several epidemiological studies reported that there is certain relationship between electromagnetic field(EMF) exposure and the development of Alzheimer's disease.The purpose of this article is to verify the possible delayed effects of EMF exposure on central nervous system(CNS) through animal experiment. METHODS:Male Kunming mice, aged 2 months old, were randomly divided into exposure group which was exposed to EMF for 20 minutes, mean power density was 8.1 mW/cm2, and the mean specific absorption rate(SAR) of the whole body was 2.4 W/kg and sham exposure group(control group).Cerebral pathomorphological observation was performed in 5 mice randomly selected from the exposure group and control group 3 days and 8 months after exposure,respectively.Immunohistochemistry for glial fibrillary acidic protein(GFAP) was performed to determine astrocytes, and imaging and quantitative analysis was also used. RESULTS:The rectal temperature before exposure[(36.4±0.25) ℃] was not significantly different from that after exposure[(36.5±0.40) ℃](t=-0.8480,P=0.4032).Quantitative and morphologic changes of GFAP positive astrocytes were significant between the exposure and control groups 3 days after exposure.Eight months later, the number of astrocytes in hippocampus was increased significantly(P< 0.01),and the formation of astrocytes as satellite to neurons was increased in the exposed group as compared with the control group.Besides,the quantitative increase,astrocytes in corpus callosum and nucleus amygdalae showed obvious morphological changes with the manifestation of remarkable hypertrophyic astrocytes with long processes.In corpus callosum, the positive staining around microvessels was deeper.In nucleus amygdalae, asrocytes were found grouped in clusters with the processes oriented similarly, and it was believed that this pattern of the astrocyte clusters was analogous to the senile plaques. CONCLUSION:Pulsed microwave exposure has delayed effects on CNS,or accelerates brain aging.

关 键 词：脉冲微波照射 小鼠 脑内星形胶质细胞 延迟效应 阿尔茨海默病 

分 类 号：R742.5[医药卫生—神经病学与精神病学]