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.

通过电生理学研究了虹鳟鱼 (Salmo gairdneri)、马苏鲑鱼 (Onchorhychus masou)、白点红点鲑 (Salvelinus leucomaenis) 和山楂 (Sebastes) 的腭神经（第七颈神经）对河豚毒素 (TTX) 和石房蛤毒素 (STX) 的味觉反应 施莱格利）。 TTX 对鲑科鱼类具有高效的味觉刺激作用。在虹鳟鱼中，TTX的阈值浓度为10^-7mol/1，并且在10^-5mol-1时引起的反应是该物种最有效的氨基酸10^-3mol/1L-脯氨酸的两倍。 STX的阈值较低，为10^-6mol/1，并且响应幅度通常较小。这种情况在jacover中得到了逆转； TTX在5×10^-4mol/1时无效，但STX非常有效，并且具有10^-6mol/1的阈值浓度。在虹鳟鱼中，交叉适应实验表明，TTX 的 iber 类型受体与检测氨基酸、乙酸、蔗糖和盐酸奎宁的受体不同。此外，即使在连续刺激的情况下，对 TTX 或 STX 的综合味觉反应（一种快速适应的阶段性反应）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。行为研究表明，鲑科鱼不吃含有 TTX 的食物。这些发现表明鱼类中存在针对 TTX 和 STX 的敏感、特异性味觉受体系统，这表明鱼类存在针对水生环境中有毒猎物的防御机制。

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。”