连续高强度微波辐射致大鼠识别记忆障碍及组织结构损伤的定量研究

Study of recognition memory impairment and structural damage induced by continuous microwave radiation

目的研究连续高强度微波辐射对大鼠识别记忆的影响及其组织结构基础。方法36只二级雄性Wistar大鼠随机分为辐射组和对照组。对辐射组大鼠进行平均功率密度为50 m W/cm^(2)的微波辐射30 min,每天1次,共计5 d。对照组大鼠与辐射组相比,除不进行微波辐射外其余条件均相同。于辐射后1 d,采用新物体识别实验范式检测大鼠的识别记忆功能;于辐射后1 d,利用光学显微镜,采用苏木素-伊红(hematoxylin-eosin,HE)染色观察大鼠海马神经元组织结构损伤,采用尼氏体甲苯胺蓝染色和定量分析技术,检测海马区神经元尼氏体平均光密度(mean optical density,MOD)改变。结果50 m W/cm^(2)连续高强度微波辐射后,大鼠新物体识别实验移动距离(P<0.05)、平均速度(P<0.05)和辨别指数(P<0.05)均显著下降。大鼠海马区神经元核固缩深染,海马神经元尼氏体MOD值显著降低(P<0.05)。结论50 m W/cm^(2)微波辐射可致大鼠海马神经元损伤并导致其识别记忆障碍。

Object To investigate the effects of continuous microwave radiation on recognition and memory of rats.Methods 36 male Wistar rats were randomly divided into 2 groups:the radiation group(n=18)and the control group(n=18).The rats in the radiation group were exposed to microwave(average power density=50 m W/cm^(2),radiation time=30 min/d)for successive 5 d.The rats in the control group were treated with the same operations of radiation group but without microwave exposure.A novel object recognition test was performed to measure the recognition memory function of rats.Meanwhile,histological examinations including HE staining and Nissel staining were implemented to qualitatively and quantitatively observe the changes of hippocampal micro-structures and neuron status,respectively.Results After 50 m W/cm^(2)continuous microwave radiation,the distance(P<0.05),the average speed(P<0.05),and discrimination index(P<0.05)of the rats in the radiation group decreased significantly compared to the ones in the control group.Morphological abnormalities such as hippocampal neuron karyopyknosis were observed in HE staining slides.The results of Nissel staining demonstrated that the mean optical density(MOD)of Nissel body decreased significantly after continuous microwave radiation.Conclusions 50 m W/cm2 continuous microwave radiation could damage hippocampal neurons of rats and lead to impairment of recognition memory.