出生前1800MHz电磁波暴露对仔鼠海马γ-氨基丁酸受体表达的影响

Effects of gestation exposure to 1800 MHz radiofrequency field on GABA receptor expression in hippocampus of offspring rats

目的探讨出生前1 800 MHz电磁波暴露对仔鼠海马γ-氨基丁酸（GABA）受体表达的影响。方法 7周龄SPF级SD雄性大鼠16只和雌性32只,以雌∶雄=2∶1交配,将孕鼠随机分为两个暴露组和两个对照组,各8只。暴露组采用1 800 MHz连续射频电磁波于孕0～20 d进行全身暴露,每天12 h,两个暴露组功率密度分别为0.5、1.0 m W/cm2,各暴露组分别设置虚拟暴露作为对照组。暴露结束后在仔鼠长至3周龄和7周龄时,每组随机抽取8只,采用免疫组化法对海马GABA受体进行染色,用图像分析系统分析海马CA1、CA3和DG区GABA受体的表达。结果 0.5 m W/cm2暴露组3周龄和7周龄仔鼠海马各区GABA受体平均光密度（MOD）值均低于对照组,差异有统计学意义（P〈0.05或P〈0.01）;1.0 m W/cm2暴露组海马各区GABA受体MOD值均高于0.5 m W/cm2组,差异有统计学意义（P〈0.01）,但与对照组差异无统计学意义（P〉0.05）。结论在本实验条件下,出生前暴露于功率密度为0.5 m W/cm2的1 800 MHz电磁波可能使3周龄和7周龄仔鼠的GABA受体在海马各区表达下调。

Objective To investigate the effects of gestation exposure to 1 800 MHz radiofrequency field on GABA receptor expression in the hippocampus of offspring rats. Methods A total of 16 male SD rats and 32 female SD rats aged seven weeks were chosen to mate, female∶male = 2∶1. The pregnant rats were randomly divided into two exposure groups and control groups,eight in each. Continuous systemic exposure was conducted in the exposed groups with 1 800 MHz radio frequency electromagnetic waves from 0 to 20 pregnant days, 12 hours per day, the power density was 0.5 m W/cm2 or 1.0 m W/cm2 and sham exposure was conducted in the corresponding control groups. When the offspring rats were three and seven weeks old,eight rats were randomly selected from each group to detect the expression of GABA receptors in the hippocampus by using immunohistochemistry method. Then the expression of GABA receptor in CA1, CA3 and DG regions of rat hippocampus was analyzed by image analysis system. Results The expression of GABA receptors in hippocampus was significant down-regulated in the 0.5 m W/cm2 exposure group at the age of three weeks and seven weeks compared with the control group, and in the1.0 m W/cm2 exposure group, no significant change was seen. Conclusion Under this experimental condition, pregnant exposure to 1800 MHz radiofrequency field with power density of 0.5 m W/cm2 may cause down-regulated expression of GABA receptors in the hippocampus of offspring rats aged three and seven weeks.