局灶性脑缺血再灌注大鼠大脑NG2和O4表达变化

目的:探讨脑缺血再灌注大鼠早期大脑少突胶质祖细胞及未成熟少突胶质细胞变化及意义。方法:以线栓法制作SD大鼠局灶性脑缺血再灌注模型(阻塞90min再灌注1d、3d和7d);用免疫荧光组织化学法检测脑缺血再灌注后早期大鼠大脑梗死中心区、梗塞周边区和缺血对侧NG2和O4阳性细胞数量。结果:脑缺血再灌注后各时间点梗死中心区NG2和O4阳性细胞数明显减少;梗塞周边区NG2和O4阳性细胞数随着再灌注时间延长而逐渐增加,再灌注3d和7d增加显著;脑梗死对侧区NG2和O4阳性细胞数无明显变化。结论:成年SD大鼠脑缺血再灌注后梗塞周边区少突胶质祖细胞及未成熟少突胶质细胞增多,可能参与缺血损伤的修复过程。

The expression of NG2and O4 in rats after focal cerebral ischemia and reperfusion

Objective; To explore the early phase change of oligodendrocyte progenitor cells and preoligodendrocytes in rats after cerebral ischemia and reperfusion. Methods: To establish focal cerebral ischemia and reperfusion model in male adult SD rats by occluding the right middle artery with 4 o ylon thread (blood flow blocked for 90 minutes and then reperfusion for 1 day, 3 day and 7day). Then to determinate NG2 of O4 positive cells in the ischemic core, ischemic penumbra and contralateral area of rats at each time-point after reperfusion by immunofluorescence histoc-hemistry. Results: The number of NGZ and O4 positive cells within the ischemic core decreases significantly at each time-point after reperfusion comparing with the control group. The number of NG2 and O4 positive cells within ischemic penumbra increases gradually after reperfusion with the significant increase at 3 days and 7 days reperfusion. There is not significant change with the number of NG2 and O4 positive cells within contralateral area. Conclusions: The marked increase of oligodendrocyte progenitor cells and preoligodendrocytes was observed in the peri-infarct area during the postischemic reperfusion period in the adult rat brain. These cells might be closely associated with adqptive repair mechanisms to ischemic injury.