Axon-Schwann cell relationship in nerve regeneration and the mechanisms for the promotion of nerve

神经再生中轴突-雪旺细胞的关系及促进神经的机制

基本信息

批准号：
08457004
负责人：
IDE Chizuka
金额：
$ 4.86万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

Adhesion molecules and trophic factors play important roles in nerve regeneration. The present study examined the localization of cadherin and alpha N-catenin for adhesion molecules, and the effects of basic fibroblast growth factors (bFGF) for nerve trophic factor. In addition the localization of subtypes of protein kinase C (PKC) was examined.Cadherin was present on the axolemma at which axons were in contact with Schwann cells or with the other axons. In the axoplasm cadherin was detected in various-sized vesicles. alpha N-catenin was distributed diffusely in the cytoplasm, with no distinct association with the axolemma. No catenin was found in the Schwann cell.bFGF enhanced the extension of the regenerating axons in the in vivo experiment using rat sciatic nerve ; in which Schwann cells had been killed by cryotreatment. In this experimental model growth cones of regenerating axons grew through the Schwann cell basal lamina tube. Schwann cells migrated behind growth cones-along axons. It was suggested that bFGF was trapped to the basal lamina, and took up through combining with the receptors on the axolemma by growth cones in contact with the inner surface of basal lamina.The allograft using the cryotreated dog common peroneal nerve revealed that the bFGF could promote the growth of regenerating axons without applying immunosuppressants.PKC subtypes (delta, epsilon, zeta) were present in the cytoplasm of the regenerating axons. PKC is considered to be involved in the extension of regenerating axons.It was revealed that the neurabin which is a molecule expressed in the synapse is also present in the growth cones. Neurabin is a F-actin binding protein and suggested to be involved in neural process extension.Demyelination and the remyelination were examined in the spinal cord dorsal funiculus.

粘附分子和营养因子在神经再生中发挥重要作用。本研究检查了钙粘蛋白和 α N-连环蛋白对粘附分子的定位，以及碱性成纤维细胞生长因子 (bFGF) 对神经营养因子的影响。此外，还检查了蛋白激酶 C (PKC) 亚型的定位。钙粘蛋白存在于轴突上，轴突在此处与雪旺细胞或其他轴突接触。在轴浆中，在各种大小的囊泡中检测到钙粘蛋白。 αN-连环蛋白广泛分布在细胞质中，与轴膜没有明显关联。雪旺细胞中未发现连环蛋白。在大鼠坐骨神经体内实验中，bFGF增强了再生轴突的延伸；其中雪旺细胞已被冷冻处理杀死。在这个实验模型中，再生轴突的生长锥通过施万细胞基底层管生长。雪旺细胞沿着轴突迁移到生长锥后面。提示bFGF被捕获到基底层，并通过与基底层内表面接触的生长锥与轴膜上的受体结合而被摄取。使用冷冻处理的狗腓总神经的同种异体移植表明bFGF可以促进再生轴突的生长，无需使用免疫抑制剂。PKC 亚型（delta、epsilon、zeta）存在于细胞质中再生轴突。 PKC被认为参与再生轴突的延伸。据揭示，在突触中表达的分子神经蛋白也存在于生长锥中。 Neurabin 是一种 F-肌动蛋白结合蛋白，被认为参与神经过程延伸。在脊髓背索中检查了脱髓鞘和髓鞘再生。