大鼠脑梗死后神经前体细胞的增殖及电针作用的实验研究

目的　研究脑梗死病灶周围及海马处神经前体细胞增殖水平的动态变化及电针治疗对其的影响。方法　采用易卒中型肾性高血压大鼠 (RHRSP) ,电凝法凝闭大脑中动脉 (MCAO)。用Garcia等的综合评分法评定大鼠的神经行为学功能 ,免疫组化观察梗死灶边缘、对侧镜区及双侧海马 5 溴脱氧尿核苷 (Bromodeoxyuridine,BrdU)标记细胞的变化。结果　MCAO后大鼠轻偏瘫 ,5天时神经行为学功能恢复正常。MCAO后梗死灶边缘、双侧镜区及双侧海马均有BrdU阳性细胞分布 ,且病灶侧多于病灶对侧 ,病灶周围分布密集。电针治疗促使梗死灶边缘BrdU阳性细胞增多 ,随着治疗时间增加细胞增多更明显。结论　脑梗死可诱导病灶周边及海马神经前体细胞增殖水平上调 ,2周内神经前体细胞随着电针治疗时间的增加而增多。神经前体细胞可能是脑梗死康复的重要物质基础。

The proliferation of neural precursor cells and the effect of electroacupuncture after acute cerebral infarction in rats

Objective To investigate the distribution and proliferation of neural precursor cells(NPCs) in perifocal area and the hippocampus, and to examine the effect of electroacupuncture(EA) on them after acute cerebral infarction. Methods Stroke prone renovascular hypertensive rats(RHRSP) were used to establish middle cerebral artery occlusion(MCAO) models by electric coagulation. EA was applied 24 hour after cerebral infarction. Neurobehavioral tests and scoring were carried out once a day since MCAO, and twice a week the next week, until performing Garcia test before decapitation. The rats were decapitated 5 days and 2 weeks respectively after EA. The BrdU positive cells in ischemic perifocal area, contralateral mirror area and the hippocampus were checked by immunohistochemistry staining. Results The Garcia scores were less than 18 until the 5th day after MCAO, and the scores in EA group were significantly higher than in the control at the second and third days. There are more BrdU positive cells in the ipsilateral ischemic perifocal areas and hippocampus than in the contralateral corresponding area(both EA group and control group: P <0 05). The NPCs congregated in the ischemic perifocal areas 2 weeks after MCAO( P <0 01). BrdU positive cells increased significantly in the ischemic perifocal areas after EA treatment( P <0 05), and increased as time went by within 2 weeks. Conclusions The proliferative NPCs in the ischemic perifocal areas and hippocampus can be induced by stroke and keeped increasing during 2 weeks of the EA. Our date indicate that an endogeneous proliferative NPCs may play an important role for recovery from stroke.