脐血间充质干细胞移植对脑梗死大鼠脑内NGF、BDNF表达的影响

目的观察脐血间充质干细胞（UCBMSCs）对脑梗死大鼠脑内NGF、BDNF表达及神经功能的影响。方法实验分假手术组、对照组、移植组，采用颈内动脉线栓法制作脑梗死大鼠模型，移植组于成模后1d、4d经尾静脉移植2×10^6UCBMSCs，假手术组和对照组尾静脉注射等量PBS，移植后7d、14d进行神经功能评分，3d、7d、14d免疫组织化学法分别计数梗死灶周边区域NGF、BDNF表达阳性细胞数。结果移植后3d对照组、移植组脑内NGF、BDNF表达阳性细胞数明显高于假手术组，移植组明显高于对照组，7d、14d逐渐下降，14d时两组比较元明显差别，大鼠神经功能较对照组改善不明显。结论脑梗死后早期移植UcBMSCs促进脑内神经营养因子的表达，但神经功能修复作用有限。

Effects of umbilical cord blood mesenchymal stem cells transplantation on the expression of NGF and BDNF in a rat cerebral infarction model

Objective To observe effects of umbilical cord blood mesenchymal stem cells （UCBMSCs ） transplantation on the expression of NGF and BDNF and neural function in a rat cerebral infarction model. Methods The rats were randomly divided into into sham-operation group （ n =6 ）, control group （ n = 6 ） and transplantation group （ n = 6 ）. The rat models of middle cerebral artery occlusion （MCAO} were established with thread occluders. The rats in transplantation group were injected via tail vein with 2 × 106 UCBMSCs individually at the 1st day,4 th day. The rats in sham-operation group and control group were injected with isopyknic PBS individually at the 1st day,4 th day. Neurological score tests were performed at the 7th day and 14th day after transplantation. The expressions of NGF,BDNF in brain tissue were detected by immunohistochemistry technique at the 3rd day,Tth day and 14th day after transplantation. Results The positive cells of NGF, BDNF expressions in control group and transplantation group were higher significantly than that in sham-operation group, the positive cells in transplantation group were higher significantly than that in control group at the 3rd day after transplantation. The positive cells gradually descend. There was no significant difference in the positive cells of NGF,BDNF expressions and neurological score be- tween control group and transplantation group at the 14tb day. Conclusions The transplantation of UCBMSCs early promoted the expression of NGF and BDNF, but its effects on nerve restoration was limited.