雌激素对脑卒中后抑郁大鼠蓝斑c-fos表达的影响

目的：探讨雌激素对脑卒中后抑郁（PSD）大鼠蓝斑c-fos基因表达的影响，以期揭示雌激素在PSD的中枢调控机制。方法：雌性SD大鼠30只，经Open-Field行为学评分随机分成对照组、PSD组和雌激素治疗组，所有大鼠均行卵巢切除术（去卵巢）。对照组为常规喂养；PSD组去卵巢后7d，采用线栓法制备局灶性脑缺血并结合孤养、束缚应激制成PSD大鼠模型；雌激素治疗组对去卵巢后的PSD大鼠模型皮下包埋雌激素释放管（17β-雌二醇维持在生理浓度）。观察雌激素对PSD大鼠自发性行为和蓝斑c-fos表达的改变。结果：与对照组比较，PSD大鼠旷场实验中水平和垂直得分明显减少，蓝斑c-fos表达明显增加。与PSD组比较，雌激素治疗组能增加大鼠在旷场实验中得分，蓝斑c-fos表达减少。结论：雌激素对PSD大鼠的脑保护作用可能与下调c-fos基因表达有关。

Effect of Estrogen on the c-fos Expression in the Locus Ceruleus of Rat of Poststroke Depression

Aim:To study the effect of estrogen on the c-fos expression in the locus ceruleus of rats of poststroke depression (PSD).Methods:30 female Sprague Dawley rats were randomly divided into control group,PSD group and estrogen treatment group according to the scores of Open-Field test.Rats in all groups were ovariectomized firstly.Then the rats in the PSD group and estrogen treatment group were duplicated into focal ischemia by means of middle cerebral artery occlusion,7 days later they received isolated feed and restraint stress for 14 days,and then the rats in estrogen treatment group received an operation to embed estrogen subcutaneously.The E_2-containing capsules produced circulating concentrations of E_2 within the range observed during the diestrous phase of the estrous cycle.After that the behavioral evaluations were done with Open-Field test,these rats were sacrificed and the brains were taken,The c-fos positive cells of the locus ceruleus were detected by S-P immunohistochemical assay.Results:The spontaneous behavior of the PSD rats decreased significantly in comparison to that of the controls (P<0.01),and the numbers of c-fos positive cell in the poststroke depression were higher than those in the control group(P<0.01),the numbers of c-fos positive cells in the estrogen treatment group were lower than those in the PSD group(P<0.01). Conclusion:The protective effect of the estrogen on the brain of PSD rats may be related to reduced expression of c-fos gene.