胚胎脊髓移植联合应用bFGF对脊髓损伤后神经再生的影响

Transplantation of Fetal Spinal Cord and Basic Fibroblast Growth Factor Promotes Nerve Regeneration after Spinal Cord Injury

目的：探讨胚胎脊髓（fetal spinal cord, FSC）移植联合外源性碱性成纤维细胞生长因子（basic fibroblast growth factor, bFGF）的应用对脊髓损伤后脊髓神经再生的影响.方法：采用大鼠胸段（T8～T11）脊髓左侧半横切损伤模型.移植供体为同种异体妊娠14 d的孕鼠,将实验动物分为3组：A组为损伤＋FSC移植组;B组为损伤＋FSC移植＋bFGF组;C组为单纯损伤组.术后1～8周每周行综合行为评分（combined behavioral score, CBS）评定大鼠功能,并取术后8周损伤区脊髓组织0.5 cm作嗜银染色及NF200免疫组织化学检查,分别标记轴突和胶质细胞,进行定量分析,观察神经纤维再生情况.结果：胚胎脊髓移植和外源性bFGF可以防止成鼠脊髓损伤后神经元的萎缩,图像分析发现其作用A、B组优于C组,可以较好的恢复神经元形态.CBS评分提示大鼠神经功能的恢复也有同样趋势,统计学分析治疗组与对照组间有显著性差异.免疫组织化学检查,术后8周A、B组NF着色点较C组密集,且没有明显的胶质增生.结论：脊髓损伤后联合应用胚胎脊髓移植和 bFGF可以防止神经元的萎缩,并且对神经纤维再生及功能的恢复有促进作用.

Objective： To study the effects of transplantation of fetal spinal cord and basic fibroblast growth factor on the nerve regeneration in spinal cord after spinal cord injury in adult rats. Method： 36 Wistar rats with hemisection of the thoracic segment of the spinal cord was performed for all the experimental rats. The rats were divided into 3 groups as follows： Group A with cord hemisection and fetal cord grafting; Group B with cord hemisection, fetal cord grafting plus bFGF;Group C with hemisection of the with hemisection cord only. Rats were sacrificed after 1 to 8 weeks combined behavioral score （CBS） was examined to evaluate the recovery of neurological function. The slides with Nissl staining were used to measure the size of the neurons. The positive cells were quantitatively analyzed with a computer image analysis system. The level of NF200 expression were detected by immunohistochemistric method. Results： The transplantation of fetal spinal cord and basic fibroblast growth factor could prevent the neurons atrophy after spinal cord in adult rats. The size of neurons in group A and B were more than that in group C （ P 〈 0.05 ） , these increases in size of neurons were paralleled with a significant improvement in neurological function recovery. Conclusion：The combination of the transplantation of fetal spinal cord and basic fibroblast growth factor can improve nerve regeneration of spinal cord after SCI.