OLIGODENDROCYTE ONTOGENY AND DIFFERENTIATION

髓鞘是围绕着轴突的多层膜鞘。 中枢神经系统和三叉神经核通过以下途径促进神经冲动的快速传导 跳跃传导。在中枢神经系统，少突胶质细胞合成， 组装并维持髓鞘作为一个复杂的解剖和 功能结构。每个少突胶质细胞各延伸几个突起 在髓鞘中终止。为了实现生产和生产 这种大量膜的定向组装，细胞在空间上 通过重新分配其合成机械来组织其合成机械 细胞骨架元素。这一假说将通过显微镜进行检验。 细胞器和细胞骨架的分布分析 少突胶质细胞中髓鞘形成不同阶段的成分。 髓鞘成分在少突胶质细胞内呈区域性分布。 和髓鞘。因此，髓鞘的合成需要分类 细胞识别特定髓鞘成分的机制 少突胶质细胞的细胞学机制和投放到髓鞘部位 集合。髓鞘碱性蛋白的分选是在 它的信使核糖核酸，被运输到髓鞘的突起 一种与少突胶质细胞骨架有关的复合体。我们建议 通过使用原位杂交来表征这种复合体， 免疫细胞化学、神经节苷脂定位和代谢抑制剂。 我们的长期目标是描绘和描述各种不同的 髓鞘形态发生的步骤。更好地理解这一过程 髓鞘的形成，以及最终的髓鞘维护和修复，可能 导致治疗，免疫化学，药物或遗传， 患有中枢神经系统和三叉神经节脱髓鞘疾病的患者，如 多发性硬化症和格林-巴利综合征，以及 治疗性放疗后脱髓鞘情况和 化疗或病毒感染。

Myelin is the multilamellar membranous sheath that surrounds axons in the CNS and the PNS, contributing to fast conduction of nerve impulses by saltatory conduction. In the CNS, the oligodendrocyte synthesizes, assembles, and maintains the myelin sheath as a complex anatomical and functional structure. Each oligodendrocyte extends several processes each terminating in a myelin sheath. In order to achieve the production and directional assembly of this large amount of membrane, the cell spatially organizes its synthetic machinery through the redistribution of its cytoskeletal elements. This hypothesis will be tested by microscopic analysis of the distribution of cellular organelles and cytoskeletal elements in oligodendrocytes at various stages of myelin formation. Myelin components are regionally distributed within the oligodendrocytes and the myelin sheath. Thus, the synthesis of myelin requires sorting mechanisms by which specific myelin components are recognized by the oligodendrocyte cellular machinery and delivered to the site of myelin assembly. The sorting of myelin basic protein takes place at the level of its mRNA, which is transported down the processes to the myelin sheath in a complex associated with the oligodendrocyte cytoskeleton. We propose to characterize this complex by the use of in situ hybridization, immunocytochemistry, E.N. localization, and metabolic inhibitors. Our long term objectives are to delineate and characterize the various steps in myelin morphogenesis. A better understanding of the process of myelin formation, and eventually of myelin maintenance and repair, could lead to therapies, immunochemical, pharmaceutical, or genetic, for patients afflicted with demyelinating diseases of the CNS and PNS, such as multiple sclerosis and Guillain-Barre syndrome, and for patients with demyelinating conditions following therapeutic irradiation and chemotherapy or viral infections.