地塞米松对脓毒血症大鼠脑皮层诱发电位及c-Fos蛋白表达的影响

Effect of dexamethasone on somatosensory evoked potential and c-Fos in septicemic rats

目的：探讨脓毒血症大鼠皮层脑诱发电位的变化和大脑皮层c-Fos蛋白表达及地塞米松（DXM）的干预效应。方法：健康成年Wistar大鼠88只，随机分为假手术组（对照组）、盲肠结扎穿孔术（CLP）组和DXM（10mg／kg）给药组，观察1、2、4、6、10h时段体感诱发电位的动态变化，并进行大脑皮层c-Fos免疫组织化学方法测定。结果：对照组大鼠引出的皮层诱发电位波是以一个正相波为主的复合波。CLP组在10hP1波的潜伏期较对照组显著延长（P〈O．05），波幅显著降低（P〈0．05）；地塞米松1h给药组P1波潜伏期较CLP1h组显著缩短（P〈0．05），而波幅与CLP 1h组比较无统计学差异。地塞米松10h给药组P1波潜伏期较CLP10h组显著缩短（P〈0．05），波幅显著增大（P〈0．05）。c-Fos对照组有少量表达，在CLP1h开始增加，4h达高峰；在DXM注射后1～2h表达明显增加，并持续至用药后10h。结论：地塞米松对大鼠脓毒血症所引起的诱发电位的变化有所改善。c-Fos可能参与脓毒血症发病中机体对神经元损伤的应激机制，DXM通过上调c-Fos蛋白具有保护神经细胞的作用。

Objective. To explore the effect of dexamethasone on somatosensory evoked potential and c-Fos in septicemic rats. Methods： 88 Wistar rats were randomly divided into control group, experimental group and DXM treatment group. The sepsis model was made by cecal ligation puncture （CLP）. The experimen- tal group and DXM treatment group were divided into 5 groups of 1, 2, 4, 6, 10 h after CLP respectively. Cerebral evoked potential （CEP） was measured. The expression of c-Fos protein in cerebral cortex was examined by the immunohistochemical technique. Results： The latencies of P1 wave were decreased significantly in DXM group of 10h as compared with those in the CLP group of 10 h （P 〈0.05）, and the amplitudes of P1 wave were increased significantly （P 〈0.05）. The expression of c-Fos protein was increased in the CLP group of 1 h, and reached a peak 4 h, and was remarkably increased between 1 and 2 hrs after dexamethasone administration. Conclusion： The c-Fos protein can be induced by CLP, which may play roles in the central nervous system development and damage in sepsis. Dexamethasone may improve the change of CEP, and has a neuroprotective effect.