血管性痴呆小鼠海马细胞外信号调节激酶免疫组化表达及其意义

Significance of Immunohistochemical Expression of ERK1 in Pyramidal Cells of the Hippocampus in Mice with Vascular Dementia

目的探讨血管性痴呆小鼠海马CA1区锥体细胞细胞外信号调节激酶1(extracellular signal-regulatedkinase 1,ERK1)的免疫组化表达及其意义。方法采用双侧颈总动脉线结反复缺血-再灌注法制备血管性痴呆(VaD)小鼠模型,共设健康对照组、假手术组及VaD模型组,利用跳台试验和水迷宫试验观测其行为学改变,应用免疫组化技术观测其海马CA1区锥体细胞ERK1的表达变化,对小鼠学习成绩和记忆成绩与ERK1免疫反应阳性锥体细胞免疫组化评分进行相关性分析。结果 VaD模型组小鼠学习、记忆成绩低于健康对照组和假手术组(P<0.05)。VaD模型组小鼠ERK1免疫反应阳性锥体细胞免疫组化评分(13.38±3.32)较健康对照组(21.21±9.15)和假手术组(21.00士7.21)明显减少(P<0.01),而且各组小鼠海马ERK1免疫反应阳性锥体细胞免疫组化评分与小鼠学习、记忆的各项参数存在相关关系。结论 VaD小鼠海马CA1区锥体细胞ERK1表达减少可能是VaD小鼠学习、记忆成绩下降的分子机制之一。

Objective To study the significance of immunohistochemical expression change of extracellular signal-regulated kinase （ERK1） in pyramidal cells of the hippocampus in vascular dementia （VaD） mice. Methods The mice were subjected for ischemia and reperfusion repeatedly by the ligation of bilateral common carotid arteries to establish the VaD models. The behavioral changes were investigated by step-down test and water maze test. The mice were divided into the normal control group, sham operated group and VaD models group. The expression change of ERK1 was observed by immunohistochemical method. Correlation analysis of the learning and memory records were studied with the score change of ERK1 positive pyramidal cells of the hippocampus, Results The ability of learning and memory in VaD mice was significanctly lower than that in normal control group and sham group （P〈0.05）. The immunohistoehemical expression of ERK1 in pyramidal cells of the hippocampus in VaD mice （13. 38±3. 32） was also lower than that in normal control group （21.21 ±9.15） and sham group （21.00±7. 21） （P〈0. 01）. There were correlations between them. Correlation is significant at the 0.01 level. Conclusions The decrease of expression of ERK1 in pyramidal cells of the hippocampus in VaD mice might be involved with the molecular mechanism of decreasing for learning and memory in VaD mice.