REGENERATION OF PARTICULAR SYNAPSES

特定突触的再生

• 批准号: 3401053
• 负责人: Kenneth J Muller
• 金额: $ 19.8万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-09-01 至 1992-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3401053
• 关键词: Hirudinea; axon; biomarker; cell migration; central nervous system; electron microscopy; electrophysiology; fluorescence; fluorescent dye /probe; glia; interneurons; laboratory rabbit; laminin; ligands; mechanoreceptors; membrane proteins; messenger RNA; microscopy; monoclonal antibody; nervous system regeneration; neural information processing; neural transmission; neuroanatomy; neurogenesis; neuronal guidance; neurons; protein biosynthesis; synapses; tissue /cell culture; Hirudinea; axon; biomarker; cell migration; central nervous system; electron microscopy; electrophysiology; fluorescence; fluorescent dye /probe; glia; interneurons; laboratory rabbit; laminin; ligands; mechanoreceptors; membrane proteins; messenger RNA; microscopy; monoclonal antibody; nervous system regeneration; neural information processing; neural transmission; neuroanatomy; neurogenesis; neuronal guidance; neurons; protein biosynthesis; synapses; tissue /cell culture

Individual neurons in the leech can regenerate severed axons to reconnect with particular neurons that are their normal synaptic targets. In many animal species injured adult neurons may at first glance seem to revert to their developmental state, but there can be important differences between adult repair and embryonic development, including differences in synaptic function. Taking advantage of identifiable cells and cell types in the leech, the proposed project addresses the questions: (1) is axon sprouting controlled by certain cells and cellular interactions, (2) are particular molecules such as leech "laminin" and surface markers on mechanosensory neurons associated with directed growth and repair, (3) do microglia play a critical role in regeneration, (4) can protein synthesis and transport in short axon systems, particularly during regeneration, be studied by injection of synthetic mRNA's, (5) how does cell structure determine synaptic function and connectivity, and (6) do mechanisms that produce successful repair recapitulate those that guide embryonic development? The methodology will include electrophysiological recording and intracellular injection of markers for subsequent light and electron microscopic examination. Growing axons and migrating cells labelled with fluorescent markers will be tracked in living preparations with the aid of low-light video enhancement. Properties of pathways and surfaces of particular cells that bind cell-specific ligands including monoclonal antibodies will be examined with electron microscopy. Identified neurons and axons will be injected with mRNA synthesized in vitro that codes for cytoplasmic and integral membrane proteins. Single cells will be killed with intracellular injection of proteases or focally lesioned with an argon laser and fluorescent dyes. The morphology of certain cells and the complex patterns of normal and regenerated synaptic contacts between them will be reconstructed with a computer. Growth of individual cells will be studied during development and compared with regeneration. Understanding mechanisms for development and accurate regeneration in the leech central nervous system might suggest ways that nerve regeneration in higher animals including humans could be made more reliable and precise.

水ech中的个别神经元可以再生切断的轴突 与特定的神经元重新连接，这些神经元是其正常的突触 目标。 在许多动物物种中，受伤的成年神经元最初可能 一眼似乎恢复了他们的发展状态，但是可以 在成人修复和胚胎之间存在重要差异 开发，包括突触功能的差异。 服用 在水ech中可识别的细胞和细胞类型的优势， 建议的项目解决了问题：（1）是轴突发芽 由某些细胞和细胞相互作用控制，（2）是 特定分子，例如水ech“层粘连蛋白”和表面标记 关于与定向生长和 维修，（3）小胶质细胞在再生中起关键作用，（4） 可以在短轴突系统中蛋白质合成和运输， 特别是在再生期间，通过注射来研究 合成mRNA，（5）细胞结构如何确定突触 功能和连通性，（6）做产生的机制 成功的维修概括了指导胚胎的那些 发展？ 该方法将包括电生理学 记录和细胞内标记的记录 光和电子显微镜检查。 生长轴突和 将跟踪用荧光标记标记的迁移单元 在借助弱光视频增强的帮助下准备工作。 结合特定细胞的途径和表面的特性 包括单克隆抗体在内的细胞特异性配体将是 用电子显微镜检查。 确定的神经元和轴突 将在体外合成的mRNA注射，以编码为代码 细胞质和整体膜蛋白。 单细胞将是 用细胞内注射蛋白酶或局部注射 用氩激光和荧光染料病变。 形态 某些细胞以及正常和再生的复杂模式 它们之间的突触接触将通过 电脑。 将研究单个细胞的生长 发展并与再生进行比较。 理解 开发和准确再生的机制 中枢神经系统可能会暗示神经再生的方法 在包括人在内的较高动物中，可以更可靠，并且 精确的。