title: Oxidative stress and antioxidant defenses in goldfish Carassius auratus during anoxia and reoxygenation.
abstract: The purpose of this work was to evaluate the response of the antioxidant system of goldfish Carassius auratus during anoxia and reoxygenation. The exposure of goldfish to 8 h of anoxia induced a 14% decrease in total glutathione levels in the kidney, although the liver, brain, and muscle were unaffected. Anoxia also resulted in increases in the activities of liver catalase, brain glucose-6-phosphate dehydrogenase, and brain glutathione peroxidase (by 38, 26, and 79%, respectively) and a decrease in kidney catalase activity (by 17.5%). After 14 h of reoxygenation, liver catalase and brain glutathione peroxidase activities remained higher than controls and several other tissue-specific changes occurred in enzyme activities. Superoxide dismutase activity was unaffected by anoxia and reoxygenation. The levels of conjugated dienes, as indicators of lipid peroxidation, increased by 114% in liver after 1 h of reoxygenation and by 75% in brain after 14 h of reoxygenation. Lipid peroxidation was unaffected in kidney and depressed during anoxia and reoxygenation (by 44-61%) in muscle. Regulation of the goldfish antioxidant system during anoxia may constitute a biochemical mechanism that minimizes oxidative stress following reoxygenation.
authors: Oxyradical Research Group, Departamento de Biologia Celular, Universidade de Brasília, Brasília, DF, 70910-900 Brazil.
authors: V I
authors: VI
authors: Lushchak
authors: L P
authors: LP
authors: Lushchak
authors: A A
authors: AA
authors: Mota
authors: M
authors: M
authors: Hermes-Lima
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001921:Brain / Q000201:enzymology; D002374:Catalase / Q000378:metabolism; D005260:Female; D005609:Free Radicals / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006054:Goldfish / Q000378:metabolism*; D000860:Hypoxia / Q000378:metabolism*; D007668:Kidney / Q000201:enzymology; D015227:Lipid Peroxidation / Q000187:drug effects / Q000502:physiology; D008099:Liver / Q000201:enzymology; D008297:Male; D018482:Muscle, Skeletal / Q000201:enzymology; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D010100:Oxygen / Q000494:pharmacology*; D011506:Proteins / Q000378:metabolism; D013045:Species Specificity; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005609:Free Radicals; D011506:Proteins; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione; D010100:Oxygen