电磁脉冲对大鼠大脑额叶皮层炎性因子TNF-α、IL-1β及NFκBp65表达的影响

Effects of electromagnetic pulse (EMP) on the expression of inflammatory factors TNF-α,IL-1β and NFκBp65 in the cerebral frontal cortex of rats

目的:研究电磁脉冲(electromagnetic pulse,EMP)的生物学效应,为免受电磁辐射损伤提供新的研究靶点。方法:成年雄性SD大鼠随机分为四组:对照组、EMP照后1 h组、EMP照后6 h组、EMP照后24 h组。通过HE染色、ELISA和Western Blot实验方法,研究EMP(400 kv/m,200个脉冲)连续辐照3 d后在不同组大鼠大脑额叶皮层神经元的组织学变化、额叶皮层组织炎性因子-肿瘤坏死因子(TNF-α)、白细胞介素-1β(IL-1β)以及NFκBp65的表达变化。结果:(1)HE染色结果显示:经EMP辐照6 h后,大脑额叶皮层内异常神经元数目增多,异常神经元细胞核边移,胞浆与细胞核深染。(2)ELISA结果显示:EMP辐照后,大脑额叶皮层内TNF-α水平随时间逐渐升高,于辐照后6 h尤为明显(P<0.05),24 h逐渐恢复至正常;IL-1β水平各实验组均较对照组明显升高,于辐照后1 h升高最为明显(P<0.05)。(3)Western Blot结果显示:经EMP辐照后,6 h组大脑额叶皮层内NFκBp65的表达明显增多,与对照组相比,差异有统计学意义(P<0.05)。结论:电磁脉冲照射会引起大鼠大脑额叶皮层神经元损伤和炎性反应,其机制可能是通过诱导NFκB活化,启动炎性反应,进而导致大脑额叶皮层神经元损伤。

Objective：To research the biological effects of electromagnetic pulse （EMP）,and provide new research targets for protecting from damage of EMP.Methods：Adult male SD rats were randomly divided into four groups：sham group,1 h group after EMP,6 h group after EMP,24 h group after EMP.After EMP radiation for 3 days at different time （400 kv/m,200 pulse）,the histologic change of the cerebral frontal cortex neurons was observed by HE staining,the level of TNF-α and IL-1β in cerebral frontal cortex was detected by ELISA.The expression levels of NFκBp65 in cerebral frontal cortex was examined by Western Blot.Results：（1） HE staining results revealed that at 6 h after EMP radiation,the number of abnormal neurons in cerebral frontal cortex was increased,and cell bodies of neurons exhibited pyknosis,which was characterized by a darkly stained nucleus and cytoplasm.（2）The results of ELISA showed that the level of TNF-oα in cerebral frontal cortex increased in a time and was obviously in the 6 h group after EMP （P 〈 0.05）.In the 24 h group after EMP,it returned to normal.The level of IL-1β in each experimental group in cerebral frontal cortex was increased compared with sham group and was significantly in the 1 h group after EMP （P 〈 0.05）.（3） The results of Western Blot showed that the expression levels of NFκBp65 in cerebral frontal cortex in the 6 h group after EMP were increased compared with sham group （P 〈 0.05）.Conclusion：EMP exposure can cause neuronal damage and inflammatory reaction in the brain frontal cortex of rat.It may start the inflammatory reaction via inducing the NF-κB activation and result in damage of the cerebral frontal cortex neurons.