title: Bioaccumulation and oxidative stress parameters in silver catfish (Rhamdia quelen) exposed to different thorium concentrations.
abstract: The objective of this study was to evaluate the effect of chronic thorium (Th) exposure on bioaccumulation, metabolism (through biochemical parameters of the muscle) and oxidative parameters (lipidic peroxidation levels and antioxidant enzymes in the gills and in the hepatic and muscular tissues) of silver catfish (Rhamdia quelen). Silver catfish juveniles were exposed to different waterborne Th levels (in microg L(-1)): 0 (control), 25.3+/-3.2, 80.6+/-12.0, 242.4+/-35.6, and 747.2+/-59.1 for 30 d. The gills and skin were the organs that accumulated the highest Th levels. The increase in the waterborne Th concentration corresponded to a progressive increase in the Th levels in the gills and kidney. Chronic Th exposure causes alterations in the oxidative parameters of silver catfish gills, which are correlated with the Th accumulation in this organ. The levels of GST decreased in the gills of fish exposed to 747.2 microg L(-1) Th and SOD activity decreased in silver catfish exposed to 242.4 and 747.2 microg L(-1) Th. In addition, the increase in the LPO in the gills exposed to 242.4 and 747.2 microg L(-1) Th suggests that higher oxidative damage occurred in the gills. However, in the liver and muscle, these alterations occurred mainly in the lowest waterborne Th level. Metabolic intermediates in the muscle were altered by Th exposure, but no clear relationship was found.
authors: Departamento de Fisiologia e Farmacologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
authors: Daiani
authors: D
authors: Kochhann
authors: Maria A
authors: MA
authors: Pavanato
authors: Susana F
authors: SF
authors: Llesuy
authors: Lizelia M
authors: LM
authors: Correa
authors: Ana P
authors: AP
authors: Konzen Riffel
authors: Vania L
authors: VL
authors: Loro
authors: Márcia F
authors: MF
authors: Mesko
authors: Erico M M
authors: EM
authors: Flores
authors: Valderi L
authors: VL
authors: Dressler
authors: Bernardo
authors: B
authors: Baldisserotto
mesh_terms: D000641:Ammonia / Q000378:metabolism; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002397:Catfishes / Q000378:metabolism*; D029941:Fish Proteins / Q000378:metabolism; D005880:Gills / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006003:Glycogen / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D018384:Oxidative Stress; D013910:Thorium / Q000378:metabolism* / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000378:metabolism* / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D029941:Fish Proteins; D014874:Water Pollutants, Chemical; D019344:Lactic Acid; D013910:Thorium; D000641:Ammonia; D006003:Glycogen; D005947:Glucose