中文摘要：

目的 研究骨髓间充质干细胞（Bone marrow mesenchymal stem cells,BMSCs）移植对脑缺血后血管生成和神经功能恢复的影响.方法 采用全骨髓贴壁法进行BMSCs原代培养,流式细胞仪鉴定BMSCs阳性抗原（CD29和CD90）及阴性抗原（CD34和CD45）;采用线栓法复制大鼠大脑中动脉阻塞（MCAO）模型,缺血90 min再灌注,分为假手术组（n=12）、模型组（n=12）和BMSCs组（n=12）.缺血后24h,BMSCs组经尾静脉注射1 ml BMSCs（1×10^6/ml）,假手术组和模型组经尾静脉注射1 ml PBS.在缺血后第1、7、14和28天分别采用改良的神经症状严重程度评分（mNSS）、角实验和粘胶揭除实验评价神经功能;缺血后第28天,采用甲苯胺蓝染色检测脑梗死体积;缺血后第14 d,免疫荧光检测缺血周边区微血管密度和血管内皮生长因子（VEGF）表达.结果 第3代BMSCs生长良好、形态均一,呈梭形,阳性抗原CD29、CD90表达率分别为98.3％、97.4％,阴性抗原CD34、CD45表达率分别为0.2％、4.8％;与模型组比较,BMSCs组大鼠在缺血后第7,14,28天mNSS评分显著降低（P＜0.01）,第14,28天右侧转身次数减少（P＜0.05）,第7天粘胶揭除时间显著缩短（P＜0.05）,脑梗死体积显著减少（P＜0.01）;缺血后第14天,模型组大鼠缺血周边区vWF阳性血管数量和VEGF免疫阳性细胞数量分别为（42.97±8.64）个/mm^2,（54.83±10.66）个/mm^2,而BMSCs组分别为（69.43±7.29）个/mm^2,（78.70±6.16）个/mm^2,两组之间差异有统计学意义（P＜0.01）.结论 BM-SCs移植能促进脑缺血后神经功能恢复,机制可能与其上调VEGF表达促进缺血周边区血管生成有关.

英文摘要：

Objective To investigate the effect of bone marrow mesenchymal stem cells （BMSCs） transplantation on angiogenesis and functional recovery after focal cerebral ischemia in rats.Methods BMSCs were isolated and cultured using the whole bone marrow adherent method,and conducted phenotypic identification using flow cytometry analysis of surface positive antigen of CD29,CD90 and the negative antigen of CD34,CD45.Rats were subjected to middle cerebral artery occlusion （MCAO） for 90 minutes,and divided into three groups randomly,the sham group,model group and BMSCs group.24 hours after cerebral ischemia,rats were injected with 1 ml BMSCs solution （1 × 10^6 cells/ml） or PBS via the tail vein.The modified neurological severity score（mNSS） test,the corner test and the adhesive tape test were used to evaluate sensorimotor function on the 1,7,14 and 28 days after ischemia.Infarcted volume was detected by toluidine blue staining,and the numbers of vWF positive microvessels and vascular endothelial growth factor （VEGF） positive cells in the ischemic boundary were determined by immunofluorescence.Results By flow cytometric analysis,the cell phenotype of passage 3 BMSCs showed that CD29,CD90,CD34 and CD45 were 98.3%,97.4%,0.2% and 4.8%,respectively.Compared with the model group,BMSCs significantly reduced the score of mNSS（P〈0.01）,the number of right turn of corner test（P〈0.05）,latency of removal adhesive tape（P〈0.05） and the infarcted volume （P〈0.01）.The numbers of vWF positive vesscls and the VEGF positive cells were （42.97±8.64）/mm^2 and （54.83± 10.66）/mm^2 at the boundary zone in model group 14 days after ischemia,respectively.BMSCs significantly increased the numbers of vWF positive vessels （（69.43± 7.29）/mm^2） and VEGF positive cells （（78.70±6.16）/mm^2,P〈0.01）.Conclusion BMSCs can improve the functions of cerebral lesions after cerebral ischemia,which may be associated with the enhanced angiogenesis and VEGF expression in the ischemic boundary.