title: Antioxidant processes of the wild tambaqui, Colossoma macropomum (Osteichthyes, Serrasalmidae) from the Amazon.
abstract: Colossoma macropomum, locally called tambaqui, is a freshwater migratory teleost that shows good tolerance to oxygen and pH changes in water, and both chemical-physical parameters change markedly during the day time and seasonal water level oscillations in the Amazon Basin. In order to obtain a general view about the basal levels of antioxidants in different tissues of wild tambaqui, enzymatic (superoxide dismutase and catalase) and non-enzymatic (alpha-tocopherol, beta-carotene, and glutathione) antioxidants and lipid peroxidation levels were assessed in the liver, blood and plasma of ten specimens collected during the dry season (September) in a pond near Manaus-AM, Brazil. Superoxide dismutase, catalase, and lipid peroxidation levels were high in the liver and low in the blood and plasma. Confirming previous results on tambaqui, catalase was detected in the blood of one specimen only. beta-Carotene was not found in any analyzed tissue, while alpha-tocopherol was found only in the liver (7.8 +/- 7.0 nmol g(-1), mean +/- S.E.M.) and plasma (4.3 +/- 0.9 nmol ml(-1)). Blood glutathione concentrations (2.4 +/- 0.17 mmol l(-1)) of tambaqui were comparable with those found in other Amazonian teleosts. Antioxidant defenses and lipid peroxidation contents from liver. blood and plasma exhibited interesting correlations. These relationships suggest that antioxidant defenses located in different tissues and in different sub-cellular compartments act in concert.
authors.affiliation: Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade do Amazonas, Manaus, AM, Brazil. jlmarcon@fua.br
authors.forename: J L
authors.initials: JL
authors.lastname: Marcon
authors.forename: D W
authors.initials: DW
authors.lastname: Filho
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D004912:Erythrocytes / Q000737:chemistry; D005978:Glutathione / Q000378:metabolism; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D015227:Lipid Peroxidation / Q000502:physiology; D008054:Lipid Peroxides / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D010088:Oxidoreductases / Q000378:metabolism*; D012487:Salmonidae / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014018:Tissue Distribution; D014810:Vitamin E / Q000378:metabolism; D019207:beta Carotene / Q000378:metabolism
chemical_list: D000975:Antioxidants; D006454:Hemoglobins; D008054:Lipid Peroxides; D017392:Thiobarbituric Acid Reactive Substances; D019207:beta Carotene; D014810:Vitamin E; D010088:Oxidoreductases; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione