title: Liver lesions produced by aflatoxins in Rana catesbeiana (bullfrog).
abstract: This study describes alterations induced in Rana catesbeiana (bullfrog) liver after extended dietary exposure to aflatoxins (AFs). Bullfrogs of both sexes were fed for 120 days a commercial chow blended with a rice bran-based mixture of AFs containing 667.0, 11.65, 141.74, and 3.53 mg/kg of AFs B1, B2, G1, and G2, respectively. Animals were sacrificed on study days 45, 90, and 120. Severe and progressive liver lesions with structural collapse, increased hepatocyte and biliary duct cell proliferation, appearance of basophilic hepatocytes, and diffuse scarring, were observed at all time points. There were no quantitative alterations in the liver melanomacrophage centers of the AFs-exposed animals. Increased amounts of lipid hydroperoxides, indicative of ongoing oxidative stress, were more evident in the Addutor magnum muscle than in the AFs-damaged livers. No tumors were found in the R. catesbeiana livers after 120 days of exposure to relatively high doses of AFs.
authors.affiliation: Núcleo de Avaliação do Impacto Ambiental sobre a Saúde Humana (TOXICAM), Faculdade de Medicina, UNESP, Botucatu 18618-000, SP, Brazil.
authors.forename: Tony Fernando
authors.initials: TF
authors.lastname: Grassi
authors.forename: Paulo Wagner
authors.initials: PW
authors.lastname: Pires
authors.forename: Luis Fernando
authors.initials: LF
authors.lastname: Barbisan
authors.forename: Maeli Dal
authors.initials: MD
authors.lastname: Pai-Silva
authors.forename: Roueda Abou
authors.initials: RA
authors.lastname: Said
authors.forename: João Lauro Viana
authors.initials: JL
authors.lastname: de Camargo
mesh_terms: D000348:Aflatoxins / Q000633:toxicity*; D000818:Animals; D001653:Bile Ducts, Intrahepatic / Q000187:drug effects / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects; D003593:Cytoplasm / Q000187:drug effects / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D022781:Hepatocytes / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D046529:Microscopy, Electron, Transmission; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D011042:Poisons / Q000633:toxicity*; D011892:Rana catesbeiana; D036401:Toxicity Tests, Chronic
chemical_list: D000348:Aflatoxins; D011042:Poisons