雌激素对大鼠脑缺血后自发抑郁行为及缺血半暗带纹状体内脑源性神经生长因子的影响

目的：探讨雌激素对大鼠脑缺血后自发性抑郁行为的作用及对缺血半暗带纹状体内脑源性神经营养因子（BDNF）表达的影响。方法：应用大脑中动脉线栓术建立大鼠脑缺血模型。脑缺血模型大鼠随机分为对照组,脑卒中组,雌激素干预（皮下注射17β-雌二醇大豆油0.1 mL,×2周）组。观察脑缺血后及雌激素干预后抑郁行为学改变,检测缺血半暗带纹状体内BDNF表达。结果：脑缺血后,大鼠强迫游泳不动时间延长。雌激素组不动时间缩短,缺血半暗带BDNF阳性细胞数明显高于脑卒中组。结论：大鼠脑缺血后可以自发产生抑郁样症状,雌激素治疗可以改善这些症状,提高缺血半暗带BDNF表达可能为其治疗机制之一。

Effects of Estradiol on Spontaneous Depressive-like Behaviors and Brain-derived Neurotrophic Expression after Focal Ischemia in Rat

Aim： To determine the effects of estradiol on endogenous depressive-like behaviors and BDNF expression in the penumbra region after focal ischemia in rat.Methods： Focal ischemia was generated by transient occlusion of middle cerebral artery（MCA）.Rats were randomly divided into control group,stroke group and estradiol treatment group.Forced swimming test were performed to assess endogenous depression-like behavior after focal ischemia and estradiol treatment.Brain-derived neurotrophic factor（BDNF） expression in the penumbra regions was examined by immunohistochemistry.Results： Ischemic rats were found to develop significantly depressive-like behavioral 3 weeks after MCAO,compared with the sham-operated control rats.Ischemia-induced depressive-like behaviors were significantly improved after estradiol administration for 14 days.A significant regulation of BDNF protein levels in the penumbra regions of striatum were also observed in MCAO animals treated with estradiol,compared with the ischemic rats treated with vehicle.Conclusion： The findings of this study provided the evidence that spontaneous post-stroke depression（PSD） can be found in rat after focal ischemia.Estradiol can improve endogenous depressive-like behaviors in ischemic rats,and these therapeutic effects of estradiol may be related to the increasing expression of BDNF in the penumbra regions after MCAO.