人参皂甙Rb1对玻璃化保存坐骨神经异体移植后神经再生的影响

Effects of ginsenoside Rb1 on sciatic nerve preserved by vitrification and nerve regeneration after allograft

[目的]探讨人参皂甙Rb1(Ginsenoside Rb1,G-Rb1)对大鼠坐骨神经玻璃化保存及异体移植后神经再生的影响。[方法]Wistar大鼠坐骨神经在0、50、100、200μg.L-1G-Rb1玻璃化液(A、B、C、D组)中,-20℃保存4周,透射电镜观察超微结构,TUNEL法检测细胞凋亡。用玻璃化保存后的坐骨神经修复对应组SD大鼠(A’、B’、C’、D’组)坐骨神经10 mm缺损。术后4、8、14周坐骨神经功能指数观察,术后16周电生理检测、再生神经组织学观察及靶肌肉运动终板观察。[结果]坐骨神经玻璃化保存4周后,A组神经脱髓鞘严重,施万细胞质膜和基底膜破坏,B、C、D组髓鞘轻微变性,施万细胞质膜和基底膜保持完整;细胞凋亡B、C、D组轻于A组,C、D组轻于B组(P<0.05),C、D组间差异无统计学意义(P>0.05)。术后不同时间坐骨神经功能指数,16周运动神经传导速度、动作电位潜伏期及波幅,运动终板数量、面积、着色,B’、C’、D’组与A’组间,C’、D’组与B’组间,差异均有统计学意义(P<0.05),而C’、D’组间差异无统计学意义(P>0.05)。透射电镜显示,A’、B’组再生有髓神经纤维较少、髓鞘较薄,结缔组织增生明显,C’、D’组再生有髓神经纤维较多、髓鞘厚,无明显结缔组织增生。[结论]G-Rb1对玻璃化保存大鼠坐骨神经具有保护作用,并能促进异体移植后神经再生。

[ Objective] To investigate the effects of Ginsenoside Rbl （G- Rbl ） on sciatic nerve preserved by vitrification and nerve regeneration after allograft in rats. [ Method] At -20℃, Wistar rat sciatic nerve segments were preserved in 0,50, 100,200 μg · L-1 G -Rbl vitrification solution （groups A, B, C and D）for 4 weeks. The sciatic nerves were observed by trans- mission electron microscope, and the apoptosis of the sciatic nerves were detected by TUNEL. The Wistar rat sciatic nerves pre- served for 4 weeks were transplanted to 10 mm sciatic nerve defect of the corresponding SD rats （groups A＇ , B＇, C＇ and D＇ ）. The sciatic functional index were observed at 4,8,14 weeks post -transplantation, the histological and the electrophysiological changes of regenerating nerve, and the motor end -plate were detected at 16 weeks post -transplantation. [ Result] Demyelina- tion, and breakdown of the basal lamina and the cytoplasmic membrane in group A was seen, but gentle denaturation of myelin sheath in groups B, C and D were present, and the basal lamina, as well as the cytoplasmic membrane remained intact. The apop- tosis index in groups B, C and D were significantly lighter than that in group A, and lighter in groups C and D than in group B （P 〈 0.05 ）, but there was no significant differences between group C and group D （ P 〉 0.05 ）. On the sciatic functional index at different time post - transplantation, the nerve conduction velocity, the latent, the amplitude, as well as the number and the area and the staining of motor end - plate at 16 weeks post - transplantation, there were significant differences between groups B＇ , C＇ , D and group A＇ , groups C＇ , D and group B＇ （P 〈 0.05 ）, and there were no significant differences between group C＇ and group D＇ （P 〉 0.05）. The observation of transmission electron microscope showed that medullated nerve fibers and thickness of myelin sheath in groups A＇ and B＇ were more thin than that in groups C＇ and D＇, and that the connective tissue hyperplasia in groups A＇ and B were more serious than that in groups C＇ and D＇. [ Conclusion ] G - Rbl has protective effect on sciatic nerve preserved by vitrification, and can improve nerve regeneration after allograft in rats.