1. Antioxidant defenses and biochemical changes in pacu (Piaractus mesopotamicus) in response to single and combined copper and hypoxia exposure.
- Author
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Garcia Sampaio F, de Lima Boijink C, Tie Oba E, Romagueira Bichara dos Santos L, Lúcia Kalinin A, and Tadeu Rantin F
- Subjects
- Animals, Catalase metabolism, Copper Sulfate blood, Erythrocyte Count, Fish Proteins metabolism, Gills enzymology, Gills metabolism, Glutathione Peroxidase metabolism, Hypoxia blood, Hypoxia enzymology, Liver enzymology, Liver metabolism, Metallothionein metabolism, Muscle Fibers, Fast-Twitch enzymology, Muscle Fibers, Fast-Twitch metabolism, Reactive Oxygen Species metabolism, Sodium-Potassium-Exchanging ATPase metabolism, Superoxide Dismutase metabolism, Water Pollutants, Chemical blood, Antioxidants metabolism, Copper Sulfate toxicity, Fishes metabolism, Gills drug effects, Hypoxia metabolism, Liver drug effects, Muscle Fibers, Fast-Twitch drug effects, Oxidative Stress drug effects, Water Pollutants, Chemical toxicity
- Abstract
The effect of combined-factors (hypoxia+copper) on the biochemical parameters and antioxidant defenses were studied in the neotropical fish Piaractus mesopotamicus. Fish were exposed for 48 h to 0.4 mg Cu(2+) L(-1) (0.4Cu), hypoxia=50 mm Hg (Hpx), and 0.4 mg Cu(2) L(-1)+hypoxia=50 mm Hg (0.4CuHpx). The exposure to 0.4Cu increased the reactive oxygen species (ROS) in the liver, accompanied by increases in superoxide dismutase (SOD) and decreases in catalase (CAT) activity, showing the influence of copper in this protection. The exposure to Hpx decreased the activity of glutathione peroxidase (GSH-Px) and CAT. Exposure to a combined-factor caused an increase in the ROS production followed by an increase in SOD and a decrease in GSH-Px and CAT. At 0.4Cu, fish presented a reduction in CAT, while in Hpx decreases in SOD, CAT and GSH-Px were observed in red muscles. Single-factors were insufficient to cause ROS production. In combined-factors, increased ROS formation and decreased SOD, CAT and GSH-Px were observed. RBC increased in all groups, but only under combined-factors was there an increase in hemoglobin. Copper plasma concentration increased in groups exposed to copper. Na(+)/K(+)-ATPase activity in gills decreased in 0.4Cu and 0.4CuHpx, and increased in Hpx. Metallothionein concentration in gills increased under combined-factors. Combined-factors caused significant disturbances in the antioxidant defenses and biochemical parameters than single-factors.
- Published
- 2008
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