DEVELOPMENTAL STUDIES OF THE VISUAL SYSTEM

视觉系统的发育研究

• 批准号: 3255899
• 负责人: RONALD E KALIL
• 金额: $ 18.26万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-07-01 至 1992-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3255899
• 关键词: action potentials; amblyopia; axon; cats; electron microscopy; gamma aminobutyrate; histochemistry /cytochemistry; immunochemistry; immunocytochemistry; lateral geniculate body; mature animal; microscopy; neuroanatomy; neurochemistry; neurogenesis; neurons; neurotransmitters; newborn animals; optic tract; retinal ganglion; synapses; visual cortex; visual deprivation; visual pathways

The research proposed here will investigate the postnatal development of the retino-geniculo-cortical pathway in the cat. Four sets of experiments are described: (1) In normal and visually deprived cats, the structural development of circuits in the dorsal lateral geniculate nucleus (LGN) and primary visual cortex (area 17) that are thought to use gamma-aminobutyric acid (GABA) as a neurotransmitter will be studied with light and electron microscopic immunocytochemistry, using specific antibodies made against GABA. (2) The effect of substituting electrical stimulation for retinal ganglion cell (RGC) action potentials on the morphological development of retinogeniculate synapses will be investigated by rearing cats with intraocular injection of tetrodotoxin (TTX), to abolish RGC action potentials, while stimulating the optic tract with implanted electrodes. In addition, the development of GABA-positive neurons and terminals in the LGN and area 17 will also be studies in TTX-injected cats using light and electron microscopic immunocytochemistry. (3) The morphology of physiologically classified retinal ganglion cells in adult cats that received a large lesion of visual cortex (areas 17, 18, and 19) at birth will be determined by direct intracellular labeling of single ganglion cells with horseradish peroxidase (HRP). (4) The synaptic organization of normal and deprived geniculocortical axons will be clarified by combining electron microscopy with the intracellular injection of HRP into physiologically identified geniculocortical fibers. The long-term objective of this research is to further our understanding of the postnatal development of the visual system under normal and abnormal conditions. Of particular interest is: (a) the role played by patterned impulse activity in the morphological development of the retino-geniculo-cortical pathway; and (b) the factors that permit compensatory reorganization in the central visual pathway after early lesions. It is intended that this work will shed light on the mechanisms that contribute to the effects of amblyopia or the sequelae that result from damage to central visual structures.

这里提出的研究将调查产后 猫视网膜-膝-皮质通路的发育。 描述了四组实验：（1）在正常和目视下 被剥夺的猫，背部回路的结构发育 外侧膝状体核 (LGN) 和初级视觉皮层（区域 17）被认为使用γ-氨基丁酸（GABA）作为 将用光和电子来研究神经递质 显微免疫细胞化学，使用制成的特异性抗体 对抗GABA。 (2) 代电效果 刺激视网膜神经节细胞（RGC）动作电位 视网膜原突触的形态发育 通过眼内注射饲养猫进行研究 河豚毒素 (TTX)，消除 RGC 动作电位，同时 用植入电极刺激视束。 在 此外，GABA 阳性神经元和末梢的发育 LGN 和 17 区也将对注射 TTX 的猫进行研究 使用光和电子显微镜免疫细胞化学。 (3) 的 生理学分类的视网膜神经节细胞的形态 视觉皮层（区域 17、 18和19）出生时将通过直接细胞内测定确定 辣根过氧化物酶标记单个神经节细胞 （辣根过氧化物酶）。 (4)突触组织的正常与剥夺 膝皮质轴突将通过结合电子来阐明 细胞内注射 HRP 进行显微镜检查 生理学上鉴定的膝皮质纤维。 这项研究的长期目标是进一步推进我们的研究 了解视觉系统的出生后发育 在正常和异常情况下。 特别令人感兴趣的是： (a) 模式化冲动活动在 视网膜-膝盖-皮质通路的形态发育； (b) 允许补偿性重组的因素 早期病变后的中央视觉通路。 其目的是 这项工作将阐明有助于实现这一目标的机制 弱视的影响或因视力受损而产生的后遗症 中央视觉结构。