摘要
目的探讨不同剂量微波连续辐射对大鼠脑功能和结构损伤远后效应的影响。方法采用0、2.5、5和10 m W/cm^2微波连续辐射220只雄性Wistar大鼠(6 min/d,30 d),于辐射后1 d、7 d、14 d、1 m、3 m、6 m、9 m和12 m,采用Morris水迷宫观察大鼠学习和记忆功能;采用多导生理记录及分析系统,对大鼠脑电图(EEG)波长、重心频率及δ波功率进行检测和分析;运用光镜及电镜观察大鼠海马结构。结果 (1)2.5 m W/cm^2组大鼠学习和记忆能力、EEG及海马组织结构于辐射后12 m内均未见明显异常(P>0.05);(2)10 m W/cm^2组辐射后3 d大鼠穿越平台次数明显减少(P<0.05),辐射后7 d、1 m、3 m和9 m,其平均逃避潜伏期明显延长(P<0.05)。(3)10 m W/cm^2组于辐射后1 m内,脑电信号中高频成分减少,低频成分增加,脑电信号整个功率谱的重心向低频迁移,脑电功率谱重心频率降低,δ波绝对能量值增大(P<0.05),3m后见恢复。(4)5 m W/cm^2和10 m W/cm^2组大鼠于辐射后6 m内,海马组织神经元固缩深染,线粒体肿胀、空化,内质网扩张,突触囊泡减少,间隙模糊,血管周间隙增宽,以辐射后7 d最重,之后呈恢复趋势,至6 m仍未恢复正常。结论 2.5 m W/cm^2微波连续辐射后大鼠学习和记忆功能、EEG和海马组织结构及超微结构未见明显改变;5 m W/cm^2和10 m W/cm^2的微波辐射可引起大鼠学习和记忆功能下降、脑电图呈抑制现象和海马组织结构损伤,且此改变与辐射剂量呈正相关。
Objective To investigate the long term effects of function and structural damages to brain from continuous radiation with different dose microwave. Methods 220 male Wistar rats were exposed to microwave at the average power density of 0,2. 5,5 and 10 m W / cm^2 for 6 min five times a week up to 6weeks. At 1 d,7 d,14 d,1 m,3 m,6 m,9 m and 12 m after last microwave exposure,the learning and memory function of rats were observed by Morris water maze,the wavelength,frequency and δ power were analyzed by electroencephalogram（ EEG）. The hippocampal structure was observed by the light microscopy and the transmission electron microscopy（ TEM）. Results Firstly,the learning and memory function,EEG and hippocampal structure of rats in 2. 5 m W / cm^2 showed no obvious abnormalities（ P 0. 05）. Secondly,rats in 10 m W / cm^2 group showed significant decrease in the number of crossings at 3 d（ P 0. 05） and prolongations in average escape latency at 7 d,1 m,3 m and 9 m（ P 0. 05）. Thirdly,the high- frequency components of EEG decreased,while the low- frequency components increased with the migration of power spectrum to low frequency,the reduction of gravity of EEG power spectrum frequency and the increase of δ power（ P 0. 05） among 1m after microwave exposure. The above changes showed recovery after 3 m. Finally,rats in 5 m W / cm^2 and 10 m W / cm^2 group showed hippocampal neuron pyknosis,mitochondrial swelling and cavitation,endoplasmic reticulum,reduction of synaptic vesicles and the width of perivascular gap. The changes of hippocampus showed worst at 7 d,and then turned to recovery. Conclusions The learning and memory function,EEG and hippocampal structure of rats in2. 5 m W / cm^2 showed no obvious changes. Rats in 5 m W / cm^2 and 10 m W / cm^2 showed the damage of learning and memory,the inhibition of EEG and the damages of hippocampal structure with the positively correlation of radiation dose.
作者
徐新萍
王惠
彭瑞云
赵黎
喻超
姚斌伟
张静
高亚兵
董霁
王浩宇
XU Xinping WANG Hui PENG Ruiyun ZHAO Li YU Chao YAO Binwei ZHANG Jing GAO Yabing DONG Ji WANG Haoyu(Beijing Institute of Radiation Medicine, Beijing 100850,China)
出处
《中国体视学与图像分析》
2016年第3期314-324,共11页
Chinese Journal of Stereology and Image Analysis
基金
国家自然科学基金资助项目(No.61401497
31570847)
