Comparison of the effects of adaptation on olfaction and taste in fish.

为了解化学感觉器官在自然条件下的功能，在不同氨基酸背景水平下，研究了海水鱼和淡水鱼的嗅觉和味觉器官对氨基酸的反应性.自适应对鱼类嗅觉和味觉的影响：以虹鳟和日本红点鲑为淡水鱼，以青鳉为海水鱼，对氨基酸的嗅觉反应随背景水平的升高而降低。嗅觉器官适应相对较慢，并被认为检测到背景水平的10%的小幅增加。随着氨基酸背景水平的增加，日本红点鲑对L-丝氨酸的嗅觉反应的刺激-背景比-反应关系向左上方移动，表明检测能力的增强。另一方面，L-脯氨酸的味觉反应随背景水平的增加而递减，10倍的背景水平增加时无反应。但对奎宁-盐酸和牛磺石胆酸的味觉反应适应较慢。因此，味觉刺激剂的种类不同，味觉刺激剂的自我适应效应也不同.虹鳟嗅球反应的频谱分析：在适应前，氨基酸化学刺激诱导的嗅球反应的峰值频率由于刺激强度而移动。在自适应过程中，峰频率的移动受氨基酸背景水平的影响，在交叉适应过程中，峰频率在某些情况下发生移动，峰频率处的功率密度发生变化或不变。这表明虹鳟鱼的嗅觉器官对刺激的种类和强度具有辨别能力。嗅球反应的频谱分析可能为理解嗅觉接收提供进一步的重要线索。

To understand the function of chemical sense organ under natural conditions, responsibility of olfactory and gustatory organs to amino acids in some marine and freshwater fish were studied electrophysiologically at various background levels of the amino acids.1. Effects of self-adaptation on olfaction and taste in fish : Rainbow trout and Japanese char as fresh water fish and greenling as marine fish were used.Olfactory responses to amino acids reduced according to the increse of backgroud level. Olfactory organ adapted comparatively slowly and were considered to detect small increase as 10% of the back-ground level. Stimulas-to-background ratio-response relationship of the olfactory response to L-serine in the Japanese char shifted upper left according to the increase of the background level of the amino acids, indicating the acceleration of ditecting ability. On the other hand, gustatory responses to L-proline reduced progressively according to the increse of backgroud level, and no response was observed to ten times increase of the background level. But gustatory responses to quinne-HCI and taurolithocholic acid adapted comparatrively slowly. So, effects of self-adaptation on gustatoin differed depending the kind of taste stimulants.2. Frequency spectral analysis of olfactory bulbar resposes in rainbow trout : Peak frequency of the olfactory bulbar responses induced by chemical stimulation with amino acid before adaptation shifted due to the stimulus intensity. During self-adaptation the shift of the peak frequency were affected by the background level of the amino acid.During crossadaptation the peak frequency shifted in some cases and power density at the peak frequency changed or unchanged. These indicate that the olfactory organ of rainbow trout discriminate the kind and intensity of the stimulus. The frequency spectral analysis of olfactory bulbar responses may provide further significant clues for undestanding olfactory reception.