Gustatory responses to tetrodotoxin and saxitoxin in fishes

鱼类对河豚毒素和石房蛤毒素的味觉反应

• 批准号: 61560221
• 负责人: YAMAMORI Kunio
• 金额: $ 1.09万
• 依托单位: School of Fisheries Sciences, Kitasato University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61560221/
• 关键词: tetrodotoxin; saxitoxin; gustatory response; taste; fish; ニジマス; ヤマメ; イワナ

The gustatory responses to tetrodotoxin (TTX) and saxitoxin (STX) recorded from the palatine nerve (VIIth caranial nerve) were studied electrophysiologically in rainbow trout (Salmo gairdneri), masu salmon (Onchorhychus masou), whitespotted char (Salvelinus leucomaenis) and jacover (Sebastes schlegeli). TTX was highly effective gustatory stimulus in salmonid fishes. In rainbow trout TTX had a threshold concentration 10^<-7> mol/1 and at 10^<-5> mol-1 evoked a response two times that of 10^<-3> mol/1 L-proline, the most potent amino acid for this species. The threshold for STX was ligher, 10^<-6> mol/1, and the response magnitude was generally small. This situation was reversed in jacover; TTX was ineffective at 5x10^<-4> mol/1, but STX was highly effective, and had a threshold concentration 10^<-6> mol/1. In rainbow trout, cross-adaptation experiments indicated that receptors of iber types for TTX are distinct from those thatdetect amino acids, acetic acid, sucrose and quinine hydrochloride. Furthermore, the integrated gustatory responses to TTX or STX, a fast-adapting, phasic response, repidly returned to the baseline even with continuous stimulation. Perfusion of the gustabory organs with these chemicals had no inhibitory effect. Behavoioral studies demonstrated that salmonid fished aviod food containing TTX. These findings indicate the existence of a sensitive, specific gustatory receptor system for TTX and STX in fishes, suggesting a defense mechanism against poisonous prey in the aquatic environment.

本文研究了虹鳟（萨尔莫）、虹鳟（Onchorhychus masou）、白斑红点鲑（Salvelinus leucomaenis）和石房蛤（Acocover）对河豚毒素（TTX）和石房蛤毒素（STX）的味觉电生理反应。TTX是鲑科鱼类高效的味觉刺激物。在虹鳟鱼中，TTX的阈值浓度为10 μ <-7>mol/l，在10 μ <-5>mol-1时，它引起的反应是10 μ <-3>mol/l L-脯氨酸的2倍，L-脯氨酸是该物种最有效的氨基酸。STX的阈值较低，为10 μ <-6>mol/l，响应幅度通常较小。这种情况在jacover中相反; TTX在5x 10 μ <-4>mol/1时无效，但STX非常有效，并且阈值浓度为10 μ <-6>mol/1。虹鳟鱼的交叉适应实验表明，TTX的受体类型与检测氨基酸、乙酸、蔗糖和盐酸奎宁的受体类型不同。此外，对TTX或STX的综合味觉反应是一种快速适应的阶段性反应，即使在连续刺激下也会迅速恢复到基线。用这些化学物质灌注味觉器官没有抑制作用。行为学研究表明，鲑科鱼类对含有TTX的食物敬而远之。这些结果表明，存在一个敏感的，特异性的味觉受体系统的TTX和STX的鱼类，建议对有毒的猎物在水环境中的防御机制。

项目成果

K.Yamamori et al.: Ann.N.Y.Acd.Sci.510. 727-729 (1988)

K.Yamamori 等人：Ann.N.Y.Acd.Sci.510。

K.Yamamori et al.: Can.J.Fish.Aquati.Sci.

K.Yamamori 等人：Can.J.Fish.Aquati.Sci。

K. Yamamori et al.: "Gustatory responses to tetrodotoxin and saxitoxin i n raihbow trout (Salmo gairdneri) and arctic char (Salvelinus alpinus) : a possible biological defense mechanism." Ann N. Y. Acd Sci.510. 727-729 (1988)

K. Yamamori 等人：“虹鳟鱼 (Salmo gairdneri) 和北极红点鲑 (Salvelinus alpinus) 对河豚毒素和石房蛤毒素的味觉反应：一种可能的生物防御机制。”