雌性和雄性大鼠脑缺血再灌注神经干细胞增殖的比较研究

目的探讨雌性和雄性成年大鼠脑缺血再灌注海马齿状回颗粒下层(subgranular zone,SGZ)、侧脑室室下层(subventricular zone,SVZ)和梗死皮质周边神经干细胞(neural stem cell,NSC)增殖的差异性.方法雌性和雄性成年大鼠各16只,制作线栓法大脑中动脉闭塞2 h后再灌注模型,用免疫组织化学方法动态检测海马齿状回SGZ、SVZ和梗死皮质周边5-溴脱氧尿嘧啶核苷(bromodeoxyuridine,BrdU)标记的阳性细胞数的变化,并采用HPIAS图像分析系统进行对比分析.结果雄性大鼠SGZ、SVZ及梗死周边区域BrdU阳性细胞在缺血再灌注3 d开始增加,7 d达到高峰,11d后开始下降,18 d进一步减少.而雌性大鼠则是3 d开始增加,7 d明显增加,11d达到高峰,18 d才开始减少,且各时间点雌性大鼠的BrdU阳性细胞数均明显高于雄性大鼠.结论脑缺血再灌注雌雄成年大鼠均有NSC增殖,雌性大鼠NSC增殖较雄性大鼠更为明显.

Comparison of the activation of neural stem cells between adult female and male rats after cerebral ischemia-reperfusion

Objective To compare the activation of NSC in SGZ, SVZ and infarction cortex boundary between adult female rats and male rats after cerebral ischemia-reperfusion. Methods There were 16 adult female rats and 16 adult male rats. Ischemia insult was accomplished by using the intraluminal filament model of MCAO and the rats were reperfused after 2 h of occlusion. Brdu-labelled cells were detected by immunohistochemistry staining at 3, 7, 11 and 18 days after reperfusion. Results The numbers of Brdu-labelled cells in SGZ, SVZ and infarct cortex boundary in male rats increased at 3 days after reperfusion, reached the peak at 7 days after reperfusion and then decreased. In female rats, the increased numbers of Brdu-labelled cells in SGZ, SVZ and infarct cortex boundary persisted for 11 days and peaked at 11 days after reperfusion. Conclusions Cerebral ischemia-reperfusion can stimulate the proliferation of NSC in both adult female rats and male rats. The activation of NSC after cerebral ischemia-reperfusion in female rats is more obvious than that in male rats.