雌激素提高去卵巢大鼠海马CA4区ERK1/2的磷酸化水平(英文)  

Estrogen Increased ERK1/2 Phosphorylation Levels in Hippocampal CA4 Region of Ovariectomized Rats

作　　者：姜明春[1] 邹宁[1] 宁炜[1] 田淑君[1] 

机构地区：[1]哈尔滨医科大学生理教研室

出　　处：《中国康复理论与实践》2007年第3期229-232,F0003,共5页Chinese Journal of Rehabilitation Theory and Practice

摘　　要：目的研究雌激素对去卵巢大鼠海马CA4区神经元细胞外信号调节激酶1/2(ERK1/2)磷酸化水平的影响。方法成年Wistar雌性大鼠随机分为正常对照组(INT)、去卵巢组(OVX)和去卵巢加雌激素组(OVX+estrogen)。用放射免疫分析方法测定血中雌二醇含量,用免疫组化检测ERK1/2的磷酸化水平。结果去卵巢组大鼠体内雌激素水平明显降低,与对照组和加雌激素组比较均有显著性差异(P<0.001);采用免疫组织化学定位检测,显示磷酸化ERK1/2主要表达在神经元胞核和胞质;免疫组化阳性细胞统计分析显示:去卵巢组大鼠海马CA4区神经元胞核和胞质着色浅,ERK1/2磷酸化水平降低,其阳性细胞计数明显减少,与对照组比较有显著性差异(P<0.001);去卵巢加雌激素组与去卵巢组相比,海马CA4区神经元胞核和胞质染色深,磷酸化ERK1/2表达阳性神经元增多(P<0.001),但仍明显低于对照组。结论雌激素提高衰老雌性大鼠脑内ERK1/2磷酸化水平,提示雌激素可通过对衰老状态下ERK信号通路的调节作用达到改善学习和记忆的目的。Objective To investigate the effects of estrogen on extracellular signal-regulated kinase-1/2（ERK1/2） phosphorylation levels in hippocampal CA4 region of ovariectomized rats. Methods Experimental female Wistar rats were randomly divided into three groups： intact （INT） group, ovariectomized （OVX） group, and OVX＋estrogen （1 mg/kg, weekly） group. Radioimmunoassay （RIA） was used to measure the estrogen content in plasma, and the levels of ERK1/2 phosphorylation were measured with immunohistochemistry. Results Compared with the control animals, the plasma estrogen level was significantly lower in OVX group （P〈0.001）. However, the plasma estrogen level was higher in the OVX＋ estrogen group than that of the OVX group （P〈0. 001）. Immunohistochemical staining showed that the phospho-ERK1/2 （p-ERK1/2） substances were present in the nucleus and cytosol of neurons. Compared with the control group, immunostaining positive cells markedly decreased in OVX group, with light nucleus and cytosol staining in the hippocampal CA4 region （P〈0. 001）. The phospho-ERK1/2 positive neurons increased more obviously in OVX＋estrogen group than in the OVX group （P〈0. 001）. Conclusion Estrogen can increase ERK1/2 phosphorylation levels in hip pocampi of aging female rats, which suggests that the ERK signal transduction pathway may be regulated by estrogen during the process of aging.

关 键 词：雌激素 去卵巢 海马 细胞外信号调节激酶(ERK) 大鼠 

分 类 号：Q492.5[生物学—生理学] R339.3[医药卫生—人体生理学]