纳米微囊缓释VEGF促血管化修复大鼠周围神经缺损的研究

Nanoencapsulated VEGF accelerating vascularization of acellular nerves in repairing peripheral nerve defect

目的评价应用纳米微囊缓释VEGF促血管化及其修复周围神经缺损的效果。方法化学去细胞神经内显微注入纳米微囊缓释VEGF,修复大鼠15 mm坐骨神经缺损为实验组(A组),对照组为化学去细胞神经显微注入VEGF组(B组)和化学去细胞神经移植组(C组),比较A、B、C组血管化时间。术后12周,检测肌电图、小腿三头肌湿重、神经微血管密度及再生轴突计数,评价其修复周围神经缺损的效果。结果术后,A组神经中心血管化的时间为7 d,B、C组为13 d。术后12周,A组神经传导速度、动作电位波幅、小腿三头肌湿重,微血管密度和神经轴突再生密度高于B、C组。结论纳米微囊缓释VEGF促进去细胞神经血管化,有利于神经轴突再生和功能恢复。

Objective To evaluate the effect of nanoencapsulated vascular endothelial growth factor （VEGF） on accelerating vascularization of acellular nerve in repairing never defect of rats. Methods The acellular nerves were micro-injected with nanoencapsulated VEGF and then were employed to repair 15 mm length sciatic nerve defect in rats （Group A）. The acellular nerves micro-injected with VEGF （Group B） and acellular nerves （Group C） served as control groups. The time to revascularization was measured. Electromyography, wet triceps surae weight, microvessel density and regenerated axon counts were examined 12 weeks after operation. Results The time to revascularization was 7 days in Group A, and 13 days in both Group B and Group C. After 12 weeks, the myelinated nerve fiber density, nerve conduction velocity, wave amplitude, microvessel density in Group A were higher than those in Group B and Group C; there were no significant differences in above indexes between Group B and Group C. Conclusion Nanoencapsulated VEGF acceleratesvascularization of acellular nerves, which facilitates axon regeneration and improve functional recovery of nerve defect in rats.