葡萄糖干预对电磁辐射所致大鼠学习记忆功能障碍的影响

Glucose intervention attenuates learning and memory dysfunction induced by electromagnetic radiation in rats

目的观察平均功率密度为30 mW/cm2的连续微波辐射对大鼠学习记忆功能和海马葡萄糖摄取(glucose uptake)的影响及葡萄糖干预作用。方法成年雄性SD大鼠48只,其中18只用于Morris水迷宫实验,分为对照组、暴露组、葡萄糖干预暴露组,每组6只;暴露组、葡萄糖干预暴露组接受平均功率密度30 mW/cm2的微波连续暴露28 d,每天20 m in,暴露结束后Morris水迷宫检测大鼠学习记忆功能变化,Morris水迷宫训练前30 m in,葡萄糖干预暴露组大鼠按500 mg/kg腹腔注射葡萄糖,对照组和暴露组腹腔注射生理盐水。另30只用于海马葡萄糖摄取实验,分为对照组,暴露7、14、21、28 d组,每组6只,分别接受0、7、14、21、28 d平均功率密度为30 mW/cm2的微波暴露,各组暴露期满后,液体闪烁计数法检测大鼠海马组织对3H-2脱氧葡萄糖(3H-2DG)的摄取量变化。结果平均功率密度为30 mW/cm2的微波连续暴露28 d后,暴露组大鼠第4、5、6、7天逃避潜伏期较对照组延长(P<0.05),葡萄糖干预暴露组大鼠逃避潜伏期较对照组差异无显著性(P>0.05);暴露组大鼠在目标象限停留时间[(18.66±2.77)s]和跨越虚拟平台次数(1.60±0.54)均较对照组[(30.75±8.02)s,(2.80±0.83)]下降(P<0.05),葡萄糖干预暴露组大鼠目标象限停留时间[(26.84±4.75)s]和跨越虚拟平台次数(3.20±1.03)较对照组无显著性差异(P>0.05)。微波暴露21 d组和28 d组大鼠海马对3H-2-D-G lu-cose摄取量[(3 959±390),(3 764±192)]较对照组(5 284±711)显著减少(P<0.05)。结论腹腔注射葡萄糖可以改善微波暴露引起的学习记忆功能障碍,海马葡萄糖摄取减少可能是电磁辐射致学习记忆功能障碍的重要因素。

Objective To investigate the change of glucose uptake in the hippocampus after whole-body exposure to 30 mW/cm2 microwave,and explore the effect of glucose intervention on learning and memory dysfunction induced by electromagnetic radiation（EMR） in rats.Methods A total of 18 adult male SD rats were randomly divided into control group,microwave exposure group（MW）,microwave exposure and glucose intervention group（MW＋GLU）,with 6 animals in each group.The rats of MW and MW＋GLU group received 30 mW/cm2 microwave exposure 20 min per day for 28 d,and then their learning and memory were detected by Morris water maze.In 30 min before training,the MW＋GLU group were administered intraperitoneally 500 mg/kg of glucose every day from the start of training.Another 30 rats received 30 mW/cm2 microwave exposure 20 min once a day were sacrificed in 0,7,14,21,and 28 d respectively,6 for each time point,and then glucose uptake in the hippocampus was determined by liquid scintillation counter.Results After exposure to 30 mW/cm2 microwave for 28 d,the escape latency of MW group was increased in 4,5,6 and 7 d after training when compared to the control（P0.05）,but there was no significant difference in MW＋GLU group and control（P0.05）.The time in target quadrant and the number of times through virtual platform were also decreased in MW group than in control（18.66±2.77 vs 30.75±8.02 s,and 1.60±0.54 vs 2.80±0.83,respectively,P0.05）,but there was no significant difference in MW＋GLU group and control（26.84±4.75 s and 3.20±1.03 respectively,P0.05）.The glucose uptake in the hippocampus was significantly decreased in 21 and 28 d after exposure compared to control（3 959±390 and 3 764±192 vs 5 284±711,P0.05）.Conclusion Glucose treatment attenuates the impairment of learning and memory induced by EMR,and the reduction of hippocampal glucose uptake may be a reason of learning and memory dysfunction induced by EMR.