ABSTRACT
Abstract Benzo[a]pyrene (B[a]P) is a petroleum derivative capable of inducing cancer in human and animals. In this work, under laboratory conditions, we analyzed the responses of Colossoma macropomum to B[a]P acute exposure through intraperitoneal injection of four different B[a]P concentrations (4, 8, 16 and 32 μmol/kg) or corn oil (control group). We analyzed expression of the ras oncogene and the Hypoxia-inducible factor-1 alpha (hif-1α) gene using quantitative real-time PCR. Additionally, liver histopathological changes and genotoxic effects were evaluated through the comet assay. Ras oncogene was overexpressed in fish exposed to 4, 8 of 16 μmol/kg B[a]P, showing 4.96, 7.10 and 6.78-fold increases, respectively. Overexpression also occurred in hif-1α in fish injected with 4 and 8 μmol/kg B[a]P, showing 8.82 and 4.64-fold increases, respectively. Histopathological damage in fish liver was classified as irreparable in fish exposed to 8, 16 and 32 μmol/kg μM B[a]P. The genotoxic damage increased in fish injected with 8 and 16 μmol/kg in comparison with the control group. Acute exposure of B[a]P was capable to interrupt the expression of ras oncogene and hif-1α, and increase DNA breaks due to tissue damage.
ABSTRACT
Os padröes eletroforéticos de hemoglobinas, os fosfatos intraeritrocitários e o efeito Bohr de sangue e hemoglobinas de Brycon cf cephalus e Brycon cf erythropterum, capturados no rio Negro, foram estudados. Foram detectadas dez fraçöes hemoglobínicas (oito anódicas e duas catódicas) em B. cf cephalus e oito fraçöes anódicas em B. cf erythropterum, através de eletroforese em gel de amido. ATP e GTP foram detectados no sangue das duas espécies, e ambos têm influência no efeito Bohr de hemoglobinas. O efeito Bohr de sangue apresentou-se similar para as duas espécies estudadas