BDNF在脱细胞同种异体神经移植物修复神经缺损后不同组织中的表达

目的探讨脱细胞同种异体神经移植物(ANA)修复大鼠坐骨神经缺损后促神经再生的分子作用机制。方法将36只Wistar大鼠随机分成6组:正常对照组,自体移植组,桥接2,4,8,12周组,每组6只,分别观测患侧L4脊髓及胫前肌内脑源性神经营养因子(BDNF)蛋白及mRNA表达。结果ANA桥接大鼠坐骨神经缺损后2周患侧脊髓内BDNF表达增高,4周时达高峰,持续到8周,然后逐渐降低,12周时仍显著高于正常对照组,与自体移植组相比无差异。而患侧胫前肌最初4周内逐渐降低,然后逐渐升高,12周时达到正常水平,与自体移植组相比无差异。BDNF mRNA的表达基本与蛋白表达一致。结论ANA具有良好的组织相容性,也许可替代自体神经修复大鼠坐骨神经长距离缺损,此作用可能与上调脊髓BDNF蛋白及mRNA表达有关。

Expression of BDNF in Different Tissues after Acellular Nerve Allografts Repairing Nerve Gap

Objective To observe the expression of brain derive neurotrophic factor(BDNF) protein and BDNFmRNA of spinal cord and muscle at different time after acellular nerve allografts(ANA) repairing the sciatic nerve gap of rats,and to discuss its mechanisms. Methods 36 wistar rats were randomly divided into six groups:normal control group,auto nerve grafts group,ANA 2w,4w,8w,12w group,6 rats each group. The expression of BDNF mRNA and protein of L 4 spinal cord and tibialis anterior at injured site were observed. Results After ANA repairing the sciatic nerve gap on rats,the expression of BDNF of spinal cord at injured site increased at 2w and was up to the highest at 4w to 8w and then decreased,but was significantly higher than that of normal control group at 12w,while compared with auto nerve graft group,the difference was not significant. There was abundance of BDNF protein in tibialis anterior of normal grown-up rats. After ANA repairing the sciatic nerve gap,the expression of BDNF in tibialis anterior decreased at the beginning and came to the lowest,and then increased gradually to normal level at 12w. The expression of BDNF mRNA was consistent with that of the protein. Conclusion BDNF from centrum is very important to nerve regeneration after ANA repairing the sciatic nerve gap on rats. The ANA has good biocompatibility,so it may substitute auto nerve grafts. Its mechanism may relate to upregulating the expression of BDNF mRNA and protein of spinal cord.