摘要目的 探讨妊娠期手机暴露对子代大鼠顶叶皮质星形胶质细胞活化的影响. 方法 12周龄Sprague-Dawley大鼠18只(雌雄各9只),按1∶1合笼.将孕鼠随机分为对照组、妊娠期短时间手机暴露组(简称短时暴露组)和妊娠期长时间手机暴露组(简称长时暴露组),每组3只.于妊娠第2～18天,短时暴露组手机每日处于通话状态6h,长时暴露组手机每日处于通话状态24 h,对照组手机始终处于待机模式.取1月龄子代大鼠顶叶皮质用于形态学观察和免疫组织化学检测,并用蛋白质印迹法检测胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)的相对表达量.使用单因素方差分析和SNK检验,对数据进行统计学分析. 结果 (1)3组子代大鼠顶叶皮质神经细胞排列整齐,细胞形态正常,胞膜完整,核膜边界清楚,染色质分布均匀,核仁清晰可见.(2)对照组和短时暴露组神经元未见明显异常,突触结构完整、清楚.长时暴露组顶叶皮质神经元细胞核出现轻微皱缩,核内部分异染色质聚集成不规则块状并出现边聚现象,神经元周围的髓鞘、轴突和树突结构未见明显改变;部分突触间隙增宽,结构模糊不清,膜上致密物减少甚至消失.(3)对照组和短时暴露组顶叶皮质中均仅有少量阳性细胞,且胞体小,突起短而少.长时暴露组子代大鼠顶叶皮质GFAP阳性细胞数量增多,细胞体较大,突起增多且长,但相邻GFAP阳性细胞的突起并不相互重叠.短时、长时暴露组和对照组GFAP相对表达量分别为(0.41±0.04)、(0.79±0.04)和(0.37±0.03),差异有统计学意义(F=147.059,P＜0.001).两两比较显示,长时暴露组的GFAP相对表达量分别高于对照组和短时暴露组(P值均＜0.01). 结论 妊娠期长时手机暴露会使子代大鼠顶叶皮质星形胶质细胞出现活化,GFAP表达增加,并会使神经元出现超微结构改变.

abstractsObjective To evaluate the effects of gestational exposure to mobile phone radiation on astrocytes in parietal cortex of rat offspring.Methods Nine male Sprague Dawley rats were mated with nine female rats at the age of 12 weeks.Pregnant rats were randomly divided into three groups including control group,short-term gestational exposure group (STE group) and long-term gestational exposure group (LTE group) with three in each group.From day 2 to day 18 of pregnancy,rats in STE and LTE groups were exposed to a mobile phone in talking mode for 6 h and 24 h per day,respectively.Meanwhile,the mobile phone used in control group was kept in standby mode.Morphology and ultrastructure of cells in parietal cortex of 1 month-old offspring rat were studied by Nissle staining and electron microscope,respectively.Cells positive for glial fibrillary acidic protein (GFAP) and expression of GFAP in parietal cortex were detected by immunohistochemistry and Western bloting.One-way ANOVA,followed by SNK post hoc tests,were used for statistical analysis.Results (1) No significant difference in the morphology of cells in parietal cortex of rat offspring was observed among the three groups by Nissle staining.These cells were regularly arranged with intact cell membrane,clear nuclear membrane,evenly distributed chromatin and distinct nucleoli.(2) Neurons with normal morphology and intact synapse were observed in rat offspring in both control and STE groups.But condensation and migration of nuclear chromatin in neurons and blurred and widened synaptic clefts were observed in LTE group.(3) In offspring of control and STE groups,there were few GFAP-positive cells with small cell body and short processes in parietal cortex.But in LTE group,more GFAP-positive cells with large body and long processes were found.Moreover,long-term exposure to mobile phone during pregnancy resulted in enhanced GFAP expression in parietal cortex (0.79±0.04) as compared with control group (0.37±0.03) and STE group (0.41 ±0.04) (F=147.059,P＜0.001).Conclusions Long-term gestational exposure to mobile phone radiation might lead to activation of astrocytes,increased expression of GFAP and changes in the ultrastructure of neurons in parietal cortex of rat offspring.