NEUROTRANSMITTER MECHANISMS IN THE RETINA

视网膜中的神经递质机制

• 批准号: 3262777
• 负责人: STEPHEN C MASSEY
• 金额: $ 10.85万
• 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 1991-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3262777
• 关键词: Cercopithecidae; Macaca mulatta; acetylcholine; amacrine cells; autoradiography; color visions; cone cell; electrophysiology; electroretinography; evoked potentials; eye pharmacology; fluorescence microscopy; glutamates; glycine; glycine receptors; histochemistry /cytochemistry; immunochemistry; intercellular connection; laboratory rabbit; neural information processing; neural inhibition; neural initiation; neurochemistry; parasympathetic nervous system; retina; retinal bipolar neuron; retinal ganglion; rod cell; synapses; visual photoreceptor

The inner retina is a major site of neuronal processing in the visual system. Here, among a host of amacrine cells, ganglion cell receptive fields are formed, rod and cone pathways merge into one output, and other neurons respond selectively to directional stimuli. Bipolar cells are the principle elements which transmit visual activity from photoreceptors to the inner retina, but neither the identify of the bipolar cell transmitter, nor the output sign have been established. The PI proposes to investigate neuronal circuits in the inner retina using an integrated approach which includes: i) a study of ACh and glycine release to investigate the inputs to cholinergic and glycinergic amacrine cells. ii) extracellular and intracellular recording from the rabbit retina to investigate the function of post-synaptic glutamate recetors. iii) extracellular recording in the primate (monkey or baboon) retina to investigate colour vision and iv) intracellular staining and recording under microscope control. The last technique provides a method to record and stain identified neurons in the living retina, such as the cholinergic amacrine cells. This will simplify the analysis of the mechanism underlying directional selectivity. Glycine, an inhibitory transmitter is found in some bipolar cell which are thought to be excitatory. This anomaly may be explained by the study of dye coupling between glycinergic AII amacrine cells and bipolar cells. Since the gap junctions between these cells are a major site of rod input to cone pathways, the control of gap junction conductance by the dopaminergic cell A18 may act as a switch between rod and cone vision. By dual recordings, the PI will test to see if bipolar cells are inhibitory or excitatory and a pharmacological analysis will be performed to identify the bipolar cell transmitter. The goal of this proposal is to identify the neurons and transmitters of major circuits in the inner retina.

内部视网膜是神经元处理的主要部位 视觉系统。 在这里，在一系列的无聚细胞中，神经节 形成细胞接受场，杆和锥途径合并 输入一个输出，其他神经元对 方向刺激。 双极细胞是主要元素 将视觉活性从感光体传递到内部视网膜， 但是，双极细胞发射器的识别都不是 已经建立了输出标志。 PI建议研究内部视网膜中的神经元电路 使用集成方法，其中包括：i）ACH的研究 和甘氨酸释放以研究胆碱能和 糖氨基氨酸细胞。 ii）细胞外和细胞内 从兔子视网膜记录以研究 突触后谷氨酸再生体。 iii）细胞外记录 灵长类动物（猴子或狒狒）视网膜调查色觉 iv）在显微镜下细胞内染色和记录 控制。 最后一项技术提供了一种记录和染色的方法 在生活视网膜中鉴定出神经元，例如胆碱能 无小细胞。 这将简化对机制的分析 基础定向选择性。 甘氨酸，抑制性 在某些双极电池中发现了发射器，被认为是 兴奋性。 这种异常可以通过染料的研究来解释 甘氨酸能力AII无链氨酸细胞和双极细胞之间的耦合。 由于这些单元之间的间隙连接是杆的主要位点 输入锥途径，间隙连接电导的控制 通过多巴胺能细胞A18可以充当杆之间的切换 和锥形视觉。 通过双录音，PI将测试以查看是否 双极细胞是抑制性或兴奋性的，药理 将进行分析以识别双极细胞发射机。 该建议的目的是确定神经元和 内部视网膜中主要电路的发射器。