摘要
目的:探讨再生周围神经中NGF促血管生成及其有关机制。方法:用单通道的硅胶管硅胶45只Wistar大鼠1cm的坐骨神经缺损,在硅胶管内给药,并将它们随机分为四组:生理盐水组、几丁糖组(医用几丁糖简称几丁糖,此组15只,其中5只用作透射电镜观察),NGF+几丁糖组,NGF+几丁糖+抗VEGF组,每组10只,在术后14天时,用免疫组化的方法检测大鼠再生坐骨神经新生血管内皮细胞中CD34、vWf、VEGF、trkA的表达,并作半定量分析。同时用激光共聚焦扫描显微镜检测其表达情况。结果:生理盐水组、几丁糖组再生坐骨神经中的血管内皮细胞能表达TrkA、CD34、vWf、VEGF,两组间比较没有显著性差异,NGF+几丁糖组上述四抗原的表达比生理盐水组、几丁糖组有明显增加(P<0.01或P<0.05),NGF+几丁糖+抗VEGF组再生坐骨神经血管中的CD34和VEGF的表达完全被抑制,vWf、TrkA的表达与NGF+几丁糖组相比也显著减少(P<0.01)。激光共聚焦扫描发现,再生坐骨神经的血管中VEGF与CD34其表达明显而强烈,凡CD34表达阳性的,VEGF也表达阳性,VEGF的阳性表达比CD34要多。VEGF与vWf也呈明显其表达。结论:NGF能促进再生周围神经的血管生成;NGF促再生周围神经血管生成过程中,VEGF起着重要的作用,trkA、CD34也与之相关;NGF经trkA-VEGF-CD34通路来促进周围神经中毛细血管的生成;NGF促较大管径血管生成时,除经trkA-VEGF通路外,还可能存在其它途径。
Objective: This study was performed to evaluate the effects of Nerve growth factor(NGF) upon angiogenesis in the rat's regenerative sciatic nerves and these mechanism. Methods.. Forty rats are assigned randomly to one of four groups, namely, physiological saline group, chitosan group, NGF-chitosan group(This group includes 15 rats,5 rats are used to observe with transmission electron microscope) ,NGF-chitosan -antiVEGF group. The sciatic nerves 10mm defect of every rafs was bridged with silica gel conduit in the left latter limb. The blood vessel of the regenerative sciatic nerves were observed by the CD34 ,TrkA,vWf,VEGF immunohistochemical stain (brown stain) over a period of 14 days. At the same time coexpression is detected with Laser confocal scanning microcope. Results: CD34,TrkA,vWf,VEGF can be expressed in the regenerative sciatic nerves , which have not distinct difference in physiological saline group and chitosan group. And the expression of the four antigens in NGF-chitosan group are significantly more than two aforementioned groups(P〈0.01 or P〈0.05). The expression of CD34 and VEGF in NGF-chitosan -antiVEGF group were absolutely restrained in the rat's regenerative sciatic nerves,and the expression of vWf and TrkA are markedly less than NGF- chitosan group(P〈0.01) . Coexpression of CD34 and VEGF is obvious and strong by Laser confocal scanning microcope, All of the Ecs staining CD34 are stained by VEGF, but the Ecs staining VEGF are more than the Ecs staining CD34 . Coexpression of vWf and VEGF also is evident. Conclusions: NGF can promote angiogenesis of the regenerative peripheral nerves; VEGF is very important in the process of NGF promoting angiogenesis of regenerative perpheral nerve. TrkA and CD34 is important factors too; NGF signals through only TrkA-VEGF-CD34 to promote capillary in the regenerative peripheral nerves. But NGF signals through TrkA-VEGF to promote larger vessels, which is not exclusive.
出处
《脑与神经疾病杂志》
2007年第6期401-404,共4页
Journal of Brain and Nervous Diseases
基金
国家重点基础研究发展规划项目(G1999054206)