MECHANISMS OF VISUAL SYSTEM MATURATION

视觉系统成熟的机制

• 批准号: 3259720
• 负责人: Vivien A Casagrande
• 金额: $ 16.38万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-12-01 至 1991-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3259720
• 关键词: afferent nerve; axon; biological models; cell death; cell differentiation; dendrites; denervation; electron microscopy; evolution; histology; innervation; lateral geniculate body; microscopy; model design /development; neuroanatomy; neuronal transport; newborn animals; organ culture; retina; sympathetic nervous system; visual cortex; visual pathways

The overall objective of this research is to understand the mechanisms responsible for the development of cellular patterns and connections in the nervous system. The development of layers and connections in the lateral geniculate nucleus (LGN) provides an opportune system for investigation of these mechanisms, since the normal system is precisely organized and many aspects of its organization and development are well- documented. Our work on this system has led us to postulate a model that suggests the mechanisms of laminar formation. Each of the specific aims is designed to test aspects of this model in the developing LGN of tree shrews and ferrets. SPECIFIC AIM 1 will determine whether the developmental sequence of growth of afferents and dendrites supports the idea that these processes interact in a systematic way to produce interlaminar spaces. SPECIFIC AIM 2 will explore the influence of retinal afferents on LGN cell growth and spacing by: a) blocking axoplasmic transport; b) damaging discrete retinal regions; and c) examining for regional and laminar variations in the ontogenesis of cholinergic processes. SPECIFIC AIM 3 will examine the influence of developing cortical and collicular projections on interlaminar space formation by: a) deleting these inputs; b) blocking action potentials; and c) monocularly enucleating animals early in development. Finally, SPECIFIC AIM 4 will explore the feasibility of establishing an in vitro model (organotypic culture system) of the LGN to examine the development of cytoarchitecture and connections under controlled conditions. Together, these studies will clarify the mechanism of laminar development in the LGN. These results could, in turn, provide clues concerning the basic rules the produce orderly cellular patterns and connections in the nervous system. These studies are relevant not only to understanding basic mechanisms of normal visual system development, but also to understanding clinical disorders that may affect that development.

这项研究的总体目标是了解 负责细胞模式发展的机制 以及神经系统中的连接。 的发展 外侧膝状核 (LGN) 的层和连接 为调查这些问题提供了一个合适的系统 机制，因为正常系统是精确组织和 它的组织和发展的许多方面都很好 记录在案。 我们在这个系统上的工作使我们假设 表明层流形成机制的模型。 每个 具体目标旨在测试该模型的各个方面 树鼩和雪貂正在发育的 LGN。 具体目标 1 将确定发展是否 传入神经和树突的生长顺序支持了这一观点 这些过程以系统的方式相互作用以产生 层间空间。 SPECIFIC AIM 2 将探讨影响 视网膜传入细胞对 LGN 细胞生长和间距的影响：a) 阻断轴浆运输； b) 损害离散视网膜 地区； c) 检查区域和层流变化 胆碱能过程的本体发生。 具体目标 3 将 检查皮质和丘脑发育的影响 对层间空间形成的预测：a) 删除这些 输入； b) 阻断动作电位； c) 单眼 在发育早期对动物进行去核。 最后，具体 AIM 4将探索建立体外模型的可行性 LGN 模型（器官培养系统），用于检查 细胞结构和连接的发展 受控条件。 总之，这些研究将阐明层流的机制 LGN 的发展。 这些结果反过来又可以提供 有关产生有序细胞的基本规则的线索 神经系统的模式和连接。 这些研究 不仅与理解基本机制有关 正常的视觉系统发育，还需要理解 可能影响该发育的临床疾病。