异氟烷预处理增强大鼠海马内M2型小胶质细胞活化减轻电磁脉冲所致神经损伤

目的:观察异氟烷预处理是否通过增强大鼠海马内M2型小胶质细胞活化,减轻炎症反应改善电磁脉冲所致神经元损伤。方法:24只SD大鼠随机分为4组,分别为对照组(CON组)、异氟烷预处理组(IP组)和电磁脉冲照射组(EMP组)和异氟烷预处理加电磁脉冲照射组(IP+EMP组)。各组于照射后24 h进行尼氏染色;采用Western Blot和免疫荧光组织化学染色方法检测M2型小胶质细胞标志物Arg-1的表达;并采用ELISA方法测定海马组织中TNF-α和IL-1β的含量。结果:与CON组相比,EMP组海马齿状回颗粒细胞的尼氏体明显减少,而与EMP组相比,IP+EMP组海马齿状回颗粒细胞的尼氏体明显增多增大。Western Blot结果显示:与CON组相比,EMP组海马内Arg-1蛋白的表达明显减少(P0.05),与EMP组相比,IP+EMP组Arg-1蛋白的表达明显增加(P0.05)。免疫荧光染色结果显示:与CON组相比,EMP组海马内Arg-1的表达减弱;而与EMP组相比,IP+EMP组Arg-1的表达明显增强。EMP组海马组织中炎症因子TNF-α和IL-1β的含量较CON组增加(P0.05),IP+EMP组脑组织中炎症因子TNF-α和IL-1β的含量较EMP组减少(P0.05)。结论:异氟烷预处理可通过增加M2型小胶质细胞,减少脑组织中炎症因子含量,减轻EMP所致神经元损伤。

Isoflurane preconditioning enhances the activation of M2 microglia in hippocampus of rats to reduce the nerve injury caused by electromagnetic pulse

Objective:To observe whether isoflurane preconditioning improves electromagnetic pulse induced neuronal damage by enhancing the activation of M2 microglia in hippocampus of rats and reducing the inflammatory response.Metheds:24 SD rats were randomly divided into four groups:control group (CON group),isoflurane preconditioning group (IP group),electromagnetic pulse group (EMP group) and isoflurane preconditioning plus electromagnetic pulse group (IP + EMP group).Nissl staining was performed in each group 24 hours after irradiation;The expression of Arg-1 was detected by Western Blot and immunofluorescence staining,and the concentration of TNF-α and IL-13 in hippocam pus were determined by enzyme-linked immunosorbent assay.Results:Compared with the CON group,the Nissl bodies of hippocampal granule cells decreased in the EMP group;compared with EMP group,the Nissl bodies of hippocampal granule cells increased in the IP + EMP group.Western Blot showed that the expression of Arg-1 protein inEMP group was significantly decreased (P ＜ 0.05) comparing with CON group,and compared with EMP group,the expression of Arg-1 protein in IP + EMP group was significantly increased (P ＜ 0.05).Immunofluorescence staining shows that Compared with the CON group,the the expression of Arg-1 protein in the EMP group was decreased,while the expression of Arg-1 protein in IP + EMP group was significantly increased compared with the EMP group.The concentration of TNF-α and IL-1β in hippocampus were increased in the EMP group (P ＜ 0.05) comparing with CON group,and compared with the EMP group,the concentration of TNF-α and IL-1β decreased significantly in the IP + EMP group (P ＜ 0.05).Conclusion:Isoflurane preconditioning can reduce proinflammatory factor in the brain by increasing M2 microglia activation,and alleviate EMP neuronal damage.