Changes in the Profiles of Cortisol and Carbohydrates during Osmotic Adjustments in an Air-Breathing Catfish, <i>Clarias batrachus</i> in Higher Salinities

Abstract

The present study on the freshwater catfish, Clarias batrachus suggests that the ambient salinities have profound effects on carbohydrate metabolism and the corticosteroid, principally the cortisol as evidenced from the changes in the profiles of plasma cortisol and glucose including liver and muscle glycogen contents. Transfer of the catfish to higher salinities reveals a synchronous elevation of plasma glucose and cortisol, though with small lag period, which suggests that cortisol stimulates glucose elevation. Further, the increase in plasma cortisol results in a concomitant decline in the liver glycogen and vice versa suggesting thereby a more pronounced catabolic effect of cortisol.