神经生长因子促进周围神经血管形成的实验研究

Morphological study on the angiogenesis of peripheral nerve affected by nerve growth factor

[目的]探讨神经生长因子(nerve growth factor,NGF)在大鼠坐骨神经再生过程中促进血管形成的作用。[方法]利用自行研制的梭形双通道桥接管桥接36只SD大鼠坐骨神经长10mm缺损。将动物随机分为2组,A组:医用几丁糖凝胶组;B组:医用几丁糖凝胶+NGF和医用几丁糖凝胶+睫状神经营养因子(ciliary neurotrophic factor,CNTF)。术后4、8、16周观察再生神经的大体形态,并用HE染色和透射电镜观察再生神经的束间及束内血管分布。[结果]A组2支管内再生神经大体观察无明显差异,B组NGF侧再生神经外观呈粉红色或淡红色,质脆,弹性差;CNTF侧再生神经呈淡黄性,质韧,弹性佳。HE染色见NGF侧再生神经较CNTF侧再生神经排列紊乱,其束间及束内的血管较多见;超微结构示:B组NGF侧再生神经较少,但可见较多的成纤维细胞和丰富的新生血管。[结论]虽然NGF对周围神经再生的促进作用不及CNTF,但其在神经再生的早、中、晚期均具有较为明显的血管形成作用,其作用机制可能与成纤维细胞增殖密切相关。

[ Objective ] To discuss the effects of angiogenesis about nerve growth factor （NGF） during the peripheral nerve regeneration. [ Method] Thirty-six Sprague-Dawley rats with 10mm gap of sciatic nerve were randomly divided into two groups which had been bridged with the new double channel nerve conduit of fusiform shape. Each group contained eighteen animals, in the first group,200 ul of chitin for medical use was injected into the conduit,in the second group,the two branches of the conduit contained 100ul of the chitin and 5ul NGF or ciliary neurotrophic factor（CNTF）. At four, eight or sixteen week after operation, the angiogenesis of NGF was evaluated with Hematoxylin and Eosin（HE） staining and electron microscope. [ Result] There were not significant differences of the regenerative nerve fibres between two channels in the first groups, but in the second group, the regenerative nerve of NGF branch channel was red, crisp and the nerve of CNTF branch channel was yellow and tenacious. HE staining showed that there were much more new vessel in the regemerative nerve tract of NGF the branch channel, and the regernerative nerve fibre was disorder, there were much more fibroblasts and vessels observed under eletron microscope. [ Conclusion ] NGF can significantly promote the angiogenesis during the peripheral nerve regeneration ,the mechanism may be related to fibroblast.