CHOLINERGIC MECHANISMS IN THE RABBIT RETINA

兔视网膜的胆碱能机制

• 批准号: 3262775
• 负责人: STEPHEN C MASSEY
• 金额: $ 6.51万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-09-01 至 1988-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3262775
• 关键词: acetylcholine; amacrine cells; electrophysiology; electroretinography; evoked potentials; gamma aminobutyrate; neural information processing; neural inhibition; neural initiation; neuropharmacology; parasympathetic nervous system; retinal bipolar neuron; retinal ganglion

The cholinergic neurons of the rabbit retina, also known as starburst amacrine cells on account of their unique morphology, are a class of excitatory amacrine cells which provide a direct input to certain types of ganglion cells, including the directionally selective group. At the present time, the function of the cholinergic amacrine cells and the role of ACh in regulating ganglion cell firing rate are unknown. The PI proposes to conduct a pharmacological investigation of the cholinergic system in the rabbit retina using a broadly integrated approach which includes: 1) a study of the mechanisms controlling ACh release and 2) recording from individual neurons to evaluate the effects of cholinergic input. Using a well established release technique, the PI will identify the excitatory input to the cholinergic amacrine cells. Since this system is known to receive direct input from bipolar cells, these experiments will also provide information on the identity of the bipolar cell transmitter. Single flash experiments will be used to separate the ON and OFF components in the light-evoked release of ACh. This will permit a comparison of the excitatory and inhibitory inputs to the displaced (ON) and conventional (OFF) cholinergic amacrine cells. By extracellular recording, combined with pharmacology, the PI will compare the light-driven cholinergic input to brisk and complex ganglion cells. Specific experiments will be conducted to investigate interactions between the cholinergic and GABAergic systems. By intracellular recording, the PI will test the hypothesis that only ganglion cells receive cholinergic input. The mechanism of cholinergic excitation may be deduced by measuring changes in input resistance. For directionally selective ganglion cells, ACh and GABA inputs will be isolated and compared. The goal of these experiments is to understand the function of the cholinergic neurons in the rabbit retina. This will be one step toward an understanding of the neuronal circuits which underlie the receptive field properties of retinal ganglion cells.

兔视网膜的胆碱能神经元，也称为Starburst 由于其独特的形态，无聚细胞是一类 兴奋性无链氨酸细胞，可直接输入某些类型的 神经节细胞，包括定向选择组。 在 当前的时间，胆碱能无氨​​酸细胞的功能和作用 调节神经节细胞发射率的ACH尚不清楚。 pi 建议对胆碱能的药理研究 兔子视网膜中的系统使用广泛集成的方法 包括：1）控制ACH释放的机制和2） 从单个神经元记录以评估胆碱能的影响 输入。 使用良好的发行技术，PI将确定 对胆碱能细胞细胞的兴奋性输入。 因为这个系统是 已知可以从双极细胞中获得直接输入，这些实验将 还提供有关双极细胞发射器的身份的信息。 单个Flash实验将用于分离开关组件 在轻度诱发的ACH释放中。 这将允许比较 对流离失所（ON）和常规的兴奋性和抑制性输入 （OFF）胆碱能分枝蛋白细胞。 通过细胞外记录，结合药理学，PI将比较 轻度驱动的胆碱能输入对快速和复杂的神经节细胞。 将进行特定的实验以研究 胆碱能和GABA能系统。 通过细胞内记录，PI 将测试只有神经节细胞接受胆碱能的假设 输入。 可以通过测量来推导胆碱能激发的机制 输入电阻的变化。 对于定向选择性神经节细胞， ACH和GABA输入将被隔离并进行比较。 这些实验的目的是了解 兔视网膜中的胆碱能神经元。 这将是迈向一个 了解接受场的神经元电路 视网膜神经节细胞的特性。