ISSN:
1432-136X
Keywords:
Key words Hypoxia
;
Catecholamines
;
Glycogenolysis
;
Lipolysis
;
Fish: carp and trout
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
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 ⋅ ml-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 ⋅ l-1) were increased modestly whereas levels of free fatty acids (0.25 mmol ⋅ l-1) were decreased to 0.15 mmol ⋅ l-1. In carp, however, a marked and prolonged hyperglycaemia (from 5 to 10 mmol ⋅ l-1) and a significant continuous depression of plasma levels of free fatty acids (from 0.4 to 0.2 mmol ⋅ l-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 probably a reduction of lipolytic activity, which appears to be an adaptation to hypoxia.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s003600050031
Permalink
