Henley J M, Lindstrom J M, Oswald R E
Science. 1986 Jun 27;232(4758):1627-9. doi: 10.1126/science.3715468.
Previous studies have suggested that the retinotectal system of the goldfish contains a nicotinic acetylcholine receptor (nAChR) that is sensitive to alpha-bungarotoxin. Extracellularly recorded field potentials elicited in response to visual stimulation can be blocked by alpha-bungarotoxin, and alpha-bungarotoxin can interfere with the maintenance of retinotectal synaptic connections. Whether the transmission between the retinal ganglion cells and the tectal cells is mediated by acetylcholine and whether nAChR's exist on the dendrites of tectal cells are questions that remain. The experiments described in this report were designed to determine the site of synthesis of the nAChR's associated with the goldfish retinotectal projection. Radioactive (35S-labeled) methionine was injected into either the eye or the tectal ventricle, and the incorporation of radioactivity into the nAChR was measured by immunoprecipitation. The use of this technique provides evidence that an nAChR associated with the goldfish retinotectal projection is synthesized in the retina and transported to the optic tectum, which suggests a presynaptic site of acetylcholine action on retinal terminals.
先前的研究表明，金鱼的视网膜顶盖系统含有一种对α-银环蛇毒素敏感的烟碱型乙酰胆碱受体（nAChR）。由视觉刺激引发的细胞外记录的场电位可被α-银环蛇毒素阻断，并且α-银环蛇毒素可干扰视网膜顶盖突触连接的维持。视网膜神经节细胞与顶盖细胞之间的传递是否由乙酰胆碱介导，以及顶盖细胞的树突上是否存在nAChR，这些问题仍然存在。本报告中描述的实验旨在确定与金鱼视网膜顶盖投射相关的nAChR的合成部位。将放射性（35S标记）甲硫氨酸注入眼睛或顶盖脑室，并通过免疫沉淀法测量放射性掺入nAChR的情况。这项技术的应用提供了证据，表明与金鱼视网膜顶盖投射相关的nAChR是在视网膜中合成并运输到视顶盖，这表明乙酰胆碱在视网膜终末起作用的突触前部位。
