Substrate mobilization and hormonal changes in rainbow trout (Oncorhynchus mykiss, L.) and common carp (Cyprinus carpio, L.) during deep hypoxia and subsequent recovery

Abstract

Substrate mobilization and hormonal changes in rainbow trout(Oncorhynchus mykiss, L.) and common carp (Cyprinu$ carpio, L.) during deep hypoxia and subsequent recovery Accepted: 7 May 1996 Abstract Common carp (at 20 °C) and rainbow trout (at 15 °C) were fitted with an indwelling cannula in the dorsal aorta. The fish were exposed to a controlled decline of water pO2 followed by 90 min deep hypoxia at 0.3 kPa (carp) or 4.8 kPa (trout). Thereafter, normoxic recovery was monitored in both species for 48 h. At regular intervals blood samples were analysed for glucose, lactate, free fatty acids, adrenaline, noradrenaline and cortisol. The oxygen restriction was maximal in both species and resulted in a significant increase of plasma lactate levels. In carp, adrenaline, noradrenaline and cortisol levels increased to 2, 50, and 753 ng.m1-1 respectively during anoxia, whereas in trout these hormones increased to 12, 8 and 735 ng" ml-1 respectively during hypoxia. In hypoxic trout, the plasma levels of glucose (3 mol'1-1) were increased modestly whereas levels of free fatty acids (0.25 mmol.1-1) were decreased to 0.15 mmol.1-1. In carp, however, a marked and prolonged hyperglycaemia (from 5 to 10 retool" 1-i) and a significant continuous depression of plasma levels of free fatty acids (from 0.4 to 0.2 mmol. 1-1) were observed indicating a difference in metabolic organization. It is suggested that hyperglycaemia is likely to be the result of hepatic glycogenolysis, stimulated by circulating catecholamines and a stimulation of gluconeogenesis by cortisol during recovery. The mechanism for the decline of plasma levels of free fatty acids is most

High Blood Cortisol Levels and Low Cortisol Receptor Affinity: Is the Chub, Leuciscus cephalus, a Cortisol-Resistant Teleost?

“…Although there are no previously published data for chub with which to compare these results, the levels of plasma glucose and plasma lactate observed in unstressed chub and the changes in these metabolites which were observed in stressed chub during the present study are similar to those reported for related species, the carp (Hertz et al, 1989;Dabrowska et al, 1991;van Raaij et al, 1996) and roach . There was again evidence of a sexually dimorphic response to a stressor in that glucose levels were significantly related to sex, being higher overall in female than male chub.…”

Effects of hypoxia and subsequent recovery on turbot Scophthalmus maximus: hormonal changes and anaerobic metabolism

“…Nevertheless, the control plasma concentrations of catecholamines and cortisol, the 2 main parameters to determine stress in fish (Donaldson 1981), were close to the lowest values reported in fish (Van Raaij et al 1996). So, it could be supposed that the impact of cannulation was not significant.…”

“…Means ± SE (n = 18 at t = 0 and 6 h at the other sample times). *Values significantly different from control data at p < 0.05 studied (Van Raaij et al 1996, Van Ginneken et al 1998. Release of catecholamines from chromaffin tissues stimulated by a decrease in PaO 2 following deep hypoxia was also reported in many fish species.…”

“…A decrease in the free fatty acid pool in plasma (Mazeaud et al 1977) and a strategy of metabolic depression, which is important in some species (Van Waversveld et al 1989, Van Ginneken et al 1998) have also been reported. Most of these mechanisms are under hormonal control involving catecholamines and cortisol , Van Raaij et al 1996.…”

The effects of acute and chronic hypoxia on cortisol, glucose and lactate concentrations in different populations of three-spined stickleback

“…Cortisol, glucose and lactate concentrations were determined in WB extracts of sticklebacks exposed to two hours or seven days of hypoxia to provide an assessment of the endocrine and metabolic adjustments caused by the treatments (Sneddon and Yerbury 2004;Johansen et al 2006;Van Raaij et al 1996a). Sticklebacks from three separate populations, whose habitats were characterised by differences in the occurrence of hypoxia, were used to test whether hypoxia tolerance varied between populations.…”