神经营养素3基因修饰的神经干细胞对周围神经再生修复的影响

目的 探讨神经营养素3基因修饰的神经干细胞对周围神经再生的影响。方法 54只SD大鼠随机分为3组，造成坐骨神经切断损伤模型，神经外膜端端缝合，于小腿三头肌每周分别注射生理盐水、未被神经营养素3基因修饰的神经干细胞、及神经营养素3基因修饰的神经干细胞。术后3、6、9周动态观察坐骨神经功能指数(SFI)以了解后肢功能恢复情况、组织学切片观察、肌湿重恢复率测定、9周后吻合口神经干的电镜观察。结果 神经营养素3基因修饰的神经干细胞组动物的有髓神经纤维密度、神经组织面积、髓鞘厚度、肌湿重以及坐骨神经功能指数均显著优于未被神经营养素3基因修饰的神经干细胞组和生理盐水组，9周时差异有统计学意义。单纯神经干细胞组各项指标优于生理盐水组。结论 将神经营养素3基因修饰的神经干细胞移植于修复的周围神经，使局部释放的NT-3加快轴突再生速度以促进周围神经再生，减缓失神经支配肌肉的萎缩。

An experiment study on the repair of peripheral nerve injury by NT-3 gene modified neural stem cells

Objective To investigate the effective treatment of peripheral nerve injury with NT 3 gene modified neural stem cells and to explore the feasibility of the treatment by means of gene transfection.Methods Fifty four SD rats were divided evenly into 3 groups.The sciatic nerve transected model was made and sutured end to end with epineurium.The neural stem cells without NT 3 gene or with NT 3 gene modified were injected into triceps muscle one time a week,and saline injected as control group.The nerve trunks of stomas and triceps muscle served as specimens 3 weeks,6 weeks and 9 weeks after operation.The general and histological changes,wet muscle weight,and the postoperative function recovery of the rear limbs of rats were dynamically observed by using sciatic nerve functional index (SFI).Results In the group of NT 3 gene modified neural stem cells,the number and density of reinnervation,the area of regenerated nerve and the thickness of myelin sheath of the regenerated nerves,and the SFI were all significantly superior to those in groups of the neural stem cell and the control with the difference being significant at 9th week after operation.The above parameters in the group of neural stem cells were superior to those in the control group.Conclusion NT 3 gene modified neural stem cells could be used in the treatment of peripheral nerve injury.It can accelerate the growth of axis cylinder and defer the atrophy of muscles.