神经节苷脂对脑缺血再灌注大鼠海马CREB表达的影响

目的探讨单唾液酸神经节苷脂(GM1)对脑缺血再灌注大鼠海马cAMP反应元件结合蛋白(CREB)表达的影响。方法 72只SD大鼠随机分为:假手术组(Sham,8只)、神经节苷脂治疗组(GM1,32只)、缺血再灌注组(I/R,32只)。GM1治疗组和I/R组依据缺血后再灌注的不同时间点再细分为6h、12h,24h、3d,共4个小组。应用免疫组织化学方法和Western blot方法检测各组大鼠海马CREB蛋白的表达。结果免疫组织化学方法检测时发现,缺血处理后,CREB表达水平迅速增高,在6h时最高,之后持续激活,至12h时开始降低,与假手术组相比,CREB阳性产物的平均光密度值(MOD)显著升高(P0.01);与相同时间点的缺血组比较,GM1治疗组的CREB蛋白阳性表达水平明显升高(P0.01)。Western blot方法也得到了相同的结论。结论 GM1对脑缺血再灌注损伤的神经保护作用可能与上调CREB蛋白的表达相关。

The effect of monosialoganglioside on the expression of CREB in hippocampus of cerebral ischemia-reperfusion rat

Objective To study the effect of monosialoganglioside（GM1） on the expression of cAMP response element binding protein（CREB） in hippocampus of cerebral ischemia-reperfusion rat to explore the possible mechanism of Gml protective effect on cerebral ischemia-reperfusion. Methods 72 SD rats were randomly divided into the sham group, ischemia-reperfusion group（I/R） and GM1 group at different time points （6h, 12h, 24h, 3d） after reperfusion. The expression of CREB in hippocampus of all groups was examined by immunochemistry and Western blot methods. Results The expression level of CREB in hippocampus was increased after GM1 was injected （P〈0.01）, reached peak at 6h, then sustained a high level, decreased at 12h after reperfusion. The mean optic density（MOD） of CREB positive product in hippocampus was higher in I/R group than in sham group, increased significantly in GM1 group than in I/R group at the same time point（P〈O.01）; and the same results was obtained by Western blot. Conclusion The protective effect of GM1 on the cerebral ischemia-reperfusion injury might be related to the upregulation of CREB expression.