STRUCTURE AND FUNCTION IN RETINAL NEURONS

视网膜神经元表达独特的反应 神经递质。谷氨酸会引起超极化，也会引起 去极化。GABA的反应通常是 对敌手不敏感。该项目的目标是：1)研究回应 视网膜神经元对外源性药物刺激的反应，以及 自然光刺激，以及2)了解两者之间的关系 视网膜神经元上受体的表达，神经回路 视网膜和视网膜信息处理任务。这项研究检查了 从大鼠和斑马鱼中急性分离的视网膜神经元，以及 斑马鱼视网膜切片中发现的原位神经元。尖锐地 分离的双极细胞和水平细胞保持其形状并可以 在培养中进行形态鉴定。视网膜切片中的细胞 通过细胞内注射染料进行形态鉴定 记录电极。分离细胞的生理反应是 用电压敏感探针法测定；全细胞膜片钳 这项技术被用来记录视网膜神经元的反应 切成薄片。通过以下途径传播视网膜神经生物学知识 Webvision，一个基于互联网的教程，仍然是一个 本项目的副目标。有四种谷氨酸受体类型 斑马鱼双极细胞树突的全细胞斑块鉴定 视网膜切片和局部充气的钳夹记录：1.a 假定离开双极时，电导增加(EREV~0 mV)。 这种反应是红藻氨酸敏感的，CNQX被阻断。2.安邦 推测APB样电导下降(EREV~0 mV) 双极星。3.谷氨酸门控氯化物电导增加 推定为双极子。4.机构2和3的组合 推定为双极子。无双极细胞对NMDA有反应。一 双极细胞轴突连接总是发生在On或Off 内丛状层亚椎板适用于假定 反应极性，尽管许多轴突是多层的 在两个亚胺中都有核仁。这些发现表明， 谷氨酸传导机制在体内产生光响应 斑马鱼在双极细胞上，但不在双极细胞外，而且很可能有 内丛状层中通断信号输入的混合 亚胺a和亚胺b。

Retinal neurons express unique responses to neurotransmitters. Glutamate evokes hyperpolarizations as well as depolarizations. GABA responses are commonly antagonist-insensitive. The project goals are 1) to study responses of retinal neurons to exogenous pharmacological stimuli, as well as natural light stimuli, and 2) to understand the relationships between receptor expression on retinal neurons, the neural circuitry of retina, and retinal information-processing tasks. The study examines acutely dissociated retinal neurons from rat and zebrafish, and in-situ neurons identified in zebrafish retinal slices. Acutely dissociated bipolar and horizontal cells retain their shapes and can be morphologically identified in culture. Cells in retinal slices are identified morphologically by intracellular dye injection via the recording electrode. Physiological responses of isolated cells are assayed with voltage-sensitive probes; whole-cell patch clamp techniques are used to record the responses of neurons in the retinal slice. Dissemination of knowledge in retinal neurobiology through WEBVISION, an internet- based tutorial, continues to be a subsidiary goal of this project. Four glutamate-receptor types were identified on zebrafish bipolar-cell dendrites with whole-cell patch clamp recordings in retinal slice and localized puffs: 1. A conductance increase (Erev ~ 0mV) in presumed OFF bipolars. Such responses were kainate sensitive and CNQX blocked. 2. An APB-like conductance decrease (Erev ~ 0mV) in presumed ON bipolars. 3. A glutamate- gated chloride conductance increase in presumed ON bipolars. 4. A combination of mechanisms 2 and 3 in presumed ON bipolars. No bipolars responded to NMDA. One bipolar-cell axonal bouton always occurred in the ON or OFF inner-plexiform-layer sublamina appropriate to the presumptive response polarity, though many axons were multistratified with boutons in both sublaminae. These findings indicate a diversity of glutamate conductance mechanisms generate the light responses in zebrafish ON-, but not OFF-, bipolar cells, and that there likely is mixing of ON and OFF signal inputs in inner-plexiform-layer sublaminas a and b .