EXPERIMENTAL CONTROL OF STRESS HORMONE LEVELS IN FISHES - TECHNIQUES AND APPLICATIONS

We have attempted to critically review the methods used to experimentally control in vivo levels of circulating stress hormones (cortisol, epinephrine, norepinephrine) in fish, and to suggest which of them are most suitable for future studies (Table 4). From the discussion it is evident that there are numerous choices for achieving elevated hormone concentrations. However, the method chosen should match the temporal pattern and the degree of hormone elevation that is concordant with the type of stress one is trying to simulate; in other words be physiological. With regard to inhibition of hormone release as a tool for in vivo physiological investigations, it appears that few of these methods are suitable for widespread usage. However, surgical denervation of the chromaffin tissue, and the inhibition of cortisol synthesis by implantation of cortisol-laden pellets within the forebrain nuceli or by the administration of metopirone, hold the most promise for eliminating the release of catecholamines and cortisol respectively. © 1994 Chapman & Hall.