Mechanisms of regenerating spout formation and growth in the peripheral nerves as studied by confocal laser scanning and immunoelectron microscopy

1.兰维耶结伤后3小时开始发芽。电子致密底包层消失的节质膜，通过髓鞘和基底层之间的间隙，作为再生轴突突出并进一步延伸。即使在Ranvier结与细胞体断开的情况下，上述芽的形成也会发生，说明芽的形成不受细胞体的影响。免疫电镜显示，在兰维叶结的芽中存在突触素，提示芽的囊泡与质膜的胞外融合的可能性。蛋白激酶C β亚型在神经肌肉连接处的轴突末端被证实定位。类似地，在肌纺锤体的感觉轴突终末也存在这些亚型（α、β和γ）。Rab3A p25定位于神经肌肉交界处的活动区。此外，免疫金法证实Rabphilin-3A在突触小泡中的定位。PGP 9.5免疫组织化学显示再生轴突到神经肌肉接点的神经支配过程。除上述已发表的论文外，在再生轴突的生长锥中还发现了synaptotagmin、synapsin I、N-cadherin和整合素亚型的存在。

1.The sprouting began as early as 3 hours after injury at the node of Ranvier. The nodal plasma membrane from which the electron dense undercoating had disappeared, protruded and further extended as regenerating axons through the space between the myelin sheath and basal lamina.2.The sprout formation as above occurred even when the node of Ranvier was disconnected from the cell body, indicating that the sprout formation is independent of effects from the cell body.3.The presence of synaptophysin was demonstrated in the sprouts at the node of Ranvier by immunoelectron microscopy, suggesting the possibility of exocytotic fusion of vesicles with the plasma membrane of the sprout.4.The localization of protein kinase C beta subtype was demonstrated in the axon terminal in the neuromuscular junction. Similarly, the subtypes (alpha, beta and gamma) were present in the sensory axon terminals of the muscle spindle.5.The localization of Rab3A p25 was demonstrated at the active zone of neuromuscular junction. In addition, the localization of Rabphilin-3A at the synaptic vesicles was demonstrated by immunogold method.6.The innervation processes of regenerating axons to the neuromuscular junction were demonstrated by PGP 9.5 immunohistochemistry.7.In addition to the above findings which were published in papers, the presence of synaptotagmin, synapsin I,N-cadherin and an integrin subtype were demonstrated in the growth cone of regenerating axons.