THE ACTIVITY OF PERIPHERALLY STORED NEUROHUMORS IN CATFISHES

Area of Science:

• Zoology
• Neuroendocrinology
• Fish Biology

Background:

• Fish coloration is influenced by neurohumoral signaling.
• Understanding the storage and release mechanisms of these signals is crucial for explaining natural color changes.

Purpose of the Study:

• To investigate the effects of subcutaneous injections of adrenalin and acetylcholine in oil on catfish coloration.
• To determine if these substances are stored in the fish and influence color responses.

Main Methods:

• Subcutaneous injection of adrenalin and acetylcholine in varying concentrations mixed with olive oil into catfish.
• Observation and documentation of induced color changes (pale and dark spots, blanching).
• Assessment of the duration and reversibility of color changes, including interactions with intermedin and adrenalin.

Main Results:

• Adrenalin in oil produced pale spots and general blanching, with effects lasting weeks.
• Acetylcholine in oil, at high concentrations, produced dark spots.
• Color changes induced by adrenalin and acetylcholine in oil could be temporarily reversed, suggesting subcutaneous storage.
• Interactions with intermedin and adrenalin demonstrated the reversibility and storage of these substances.

Conclusions:

• Subcutaneous storage of adrenalin and acetylcholine in oil is indicated by the prolonged and reversible color changes in catfish.
• Natural color changes in catfish may involve neurohumors like adrenalin and acetylcholine stored in lipoids, prolonging initial color responses.