DEVELOPMENTAL STUDIES OF THE VISUAL SYSTEM

这里提出的研究旨在澄清 大鼠视网膜-膝状体-皮质通路的结构和发育 猫。计划进行四组实验：1)可能的神经递质 在视黄素生成途径中，将使用光和 电子显微镜免疫组织化学与递质特异性 逆行标记；2)脉冲阻断对大鼠的影响 视网膜原基突触的形态发育将在#年进行研究。 用眼内注射河豚毒素饲养的小猫；3) 高尔基方法将用于揭示单眼剥夺的影响 去传入对背侧神经元树突发育的影响 外侧膝状核(LGN)；4)LGN向 新生和出生早期幼猫的外侧视上区 将使用辣根过氧化物酶(HRP)逆行追踪绘制地图 方法，并将在有视力的成年猫身上进行测定 皮质在出生时被移除，无论LGN是否传递投射到外侧的细胞 视上区接受来自视网膜的直接突触输入。 这项研究的长期目标是提高对 一些潜在的视觉剥夺和影响的机制 弱视，以及除了揭示一些模式的 视觉系统用来补偿损伤的重组。 这些目标是通过研究正常的结构和发展 与旨在测量异常的直接影响的实验相一致 视觉体验或脑损伤。

The research proposed here is designed to clarify certain aspects of the structure and development of the retino-geniculo-cortical pathway in the cat. Four sets of experiments are planned: 1) Possible neurotransmitters in the retinogeniculate pathway will be investigated using light and electron microscopic immunohistochemistry and transmitter-specific retrograde labeling; 2) The effects of impulse blockade on the morphological development of retinogeniculate synapses will be studied in kittens that are reared with intraocular injections of tetrodotoxin; 3) Golgi methods will be used to reveal the effects of monocular deprivation and deafferentation on the dendritic development of neurons in the dorsal lateral geniculate nucleus (LGN); 4) The projection of the LGN to the lateral suprasylvian visual area in newborn and early postnatal kittens will be mapped using horseradish peroxidase (HRP) retrograde tracing methods, and it will be determined in adult cats that have had visual cortex removed at birth whether LGN relay cells that project to the lateral suprasylvian visual area receive direct synaptic input from the retina. The long-term objective of this research is to improve understanding of some of the mechanisms underlying the effects of visual deprivation and amblyopia, and in addition to shed some light on the modes of reorganization employed by the visual system to compensate for damage. These goals are approached by studying normal structure and development in concert with experiments designed to measure the direct effects of abnormal visual experience or brain injury.