PHYSIOLOGY OF PHOTORECEPTORS

这项建议由两部分组成。首先，我们建议研究 金鱼神经节突触受体的生理学和药理学 细胞，无论是用于培养中的酶分离细胞还是用于 完整的视网膜切片。神经节细胞的录音将用 全细胞和隔离两种模式下的膜片钳技术。我们 方案(1)，兴奋性氨基酸受体的特性 神经节细胞；(2)进一步研究抑制性氨基酸的作用 酸，包括对GABA脱敏性质的研究，以及 士的宁对GABA和甘氨酸的阻断作用机制研究， 以及对甘氨酸全电池电流噪声谱的解释。 单通道反应的术语；(3)，多肽作用的综述 以及分离的神经节细胞上的其他可能的神经递质；以及 (4)神经节细胞记录系统的研制 在金鱼视网膜切片中。在这项建议的第二部分，我们 建议使用微电极记录、体外灌流和 显微分光光度法研究黄瓜暗适应的机制 脊椎动物的杆状物和锥状物。这些实验旨在测试 暗适应水平上的“等效背景假说” 单一的感光器。我们还计划调查一个可能的角色， 细胞内钙离子浓度在控制敏感度中的作用 颜料漂白后的回收。

This proposal consists of two parts. In the first, we propose to study the physiology and pharmacology of synaptic receptors of goldfish ganglion cells, both for enzymatically dissociated cells in culture and for cells in slices of intact retina. Recordings from ganglion cells will be made with patch-clamp techniques in both the whole-cell and isolated patch modes. We plan (1), a characterization of excitatory amino acid receptors on isolated ganglion cells; (2), further study of the effects of inhibitory amino acids, including a study of the nature of GABA desensitization, an investigation of the mechanism of strychnine block for GABA and glycine, and an explanation of the noise spectrum for glycine whole-cell currents in terms of single-channel responses; (3), a survey of the effects of peptides and other putative neurotransmitters on dissociated ganglion cells; and (4), the development of a system for making recordings from ganglion cells in slices of goldfish retina. In the second part of this proposal, we propose to use microelectrode recording, external perfusion, and microspectrophotometry to elucidate the mechanism of dark adaptation in vertebrate rods and cones. These experiments are designed to test the "equivalent background hypothesis" of dark adaptation at the level of single photoreceptors. We also plan to investigate a possible role for intracellular calcium concentration in controlling sensitivity during recovery after pigment bleaching.