神经生长因子对坐骨神经挤压伤后的促再生作用

The promotional effect of nerve growth factor on regeneration of crushed sciatic nerve in rats

目的:观察肌注神经生长因子(NGF)对大鼠坐骨神经挤压伤后的促再生作用。方法:40只大鼠随机分成NGF高、中、低剂量组,正常对照和模型对照组。距坐骨切迹远端6mm处钳夹坐骨神经,使产生-4mm宽的挤压伤。NGF高、中、低剂量组分别给予8,4和2μg·kg^(-1)(1.6×10~3,8×10~2和4×10~2IU·kg^(-1)NGF,im,qd,连续56d。手术后不同时间,检测运动神经传导速度(MNCV)、坐骨神经功能指数(SFI)以及进行组织形态学评价。结果:与模型对照组相比,高剂量组在d35和d56,中剂量组在d35的MNCV均显著加快;高、中、低3个剂量组在术后d14后的SFI与模型组相比,均有统计学意义,且高剂量组恢复较明显,至d56各剂量组SFI均无明显差异;组织形态学显示,NGF治疗组神经髓鞘、轴索与正常对照组相比,未见明显差异;而模型组髓鞘出现脱失,细微结构不清晰,许旺氏细胞变性坏死。结论:肌注神经生长因子能明显促进大鼠坐骨神经纤维的再生,促进其神经功能的恢复。

Objective:To study the effects of nerve growth factor (NGF) on regeneration of crushed sciatic nerve in rats. Methods:40 rats were divided into high-dose,middle-dose and low-dose NGF-treated groups,control group and model group. The nerves were crushed at the site of 6mm distal to sciatic notch and a 4mm wide crush injuries were created. NGF was given to 3 NGF-treated groups in a dose of 8,4 and 2μg·kg-1. d -1 (1.6×103, 8×102,4×102IU·kg-1·d-1) respectively for 56d. Saline was given to the control and model groups. The promotional effects of NGF on regeneration of crushed sciatic nerve were evaluated by MNCV (the motor nerve conduction velocities) ,SFI (the sciatic functional index) and morphometric assessments.Results:In comparison with control and model group,the MNCV and SFI were increased significantly in NMF-treated groups at d35 and d56 for the former and after 14d for the latter. There was no significant change in SFI between groups in the end. There were no differences morphometrically in nerve myelinand between all groups except those including myelinoclasis, obscure in structure and degeneration of necrosis in Schwarnn's cells in model group.Conclusions:NGF stimulates nerve regeneration and promotes functional recovery of crushed sciatic nerves in rats.