三七三醇皂苷对局灶性脑缺血再灌注大鼠细胞增殖的影响

Effect of PTS on Expression of Cell Proliferation Following Focal Cerebral Ischemia-reperfusion in Rats

目的 :了解局灶性脑缺血再灌注后梗死区周围细胞增殖的动态变化 ,以及三七三醇皂苷 (PTS)对其表达的影响。方法 :采用改良的线栓法制备大脑中动脉阻塞 (MACO) 2h、不同再灌注时间段 (3d、 7d、 14d、2 8d)的大鼠短暂局灶性脑缺血 (transientfocalcerebralischemia)模型。应用 5 -溴脱氧尿嘧啶 (5 -bromod eoxyuridine,Brdu)和Brdu/Nestin免疫双标记法观察再灌注损伤后 3、 7、 14、 2 8d时大鼠神经前体细胞的增殖情况。结果 :脑缺血再灌注后 14d细胞增殖水平达到峰值 ,至再灌注 2 8d细胞增殖水平已明显回落 ,但仍较正常水平高。PTS组细胞增殖水平于再灌注后 7d～ 2 8d均较相同时间段对照组增强 (P <0 0 5 )。再灌注 7、 14d ,PTS组Brdu+/Nestin阳性细胞比例高于N .S组 (P <0 0 5 )。结论

Objective:To explore the change of cell proliferation and the effect of PTS on it after focal ischemia reperfusion around the infarct area.Metheod:The model of acute reperfusion injury after cerebral ischemia in rat was made by middle cerebral artery occlusion.All animals were allowed 2h ischemia and sacrificed after different durations of reperfusion (3,7,14,28d).Bromodeoxyuridine(Brdu)and the double-label immunohistochemical method with Brdu and Nestin were used to observe the change of cell proliferation in the adult rat brain.Results:The level of cell proliferation peaked at 14d after middle cerebral artery occlusion(MCAO)reperfusion,and decreased obviously but higher than that of normal at 28d.In contrast,the level of cell proliferation in the PTS groups up-regulated as compared with the controls (P<0.05) from 7 to 28d after reperfusion.The ratio of Brdu-labeling Nestin positive cells increased remarkably at 7,14d after reperfusion.Conclusion:PTS could enhance the level of cell proliferation after MCAO reperfusion.