Abstract:
Objective To evaluating the effect of Aroclor1254 on embryo development,histology and vitellogenin gene expression in zebrafish liver so as to provide basicdata of toxic effects of Aroclor1254 and to select sensitive markers for early detection and warning using zebrafish.
Methods Zebrafish and its embryos were exposed to different doses of Aroclor1254.Embryo development technique,histological examination and real-time quantitative polymerase chain reaction (RT-PCR) were used to detect the effect of embryonic development,morphological changes and vitellogenin (vtg) gene expression.
Results The zebrafish embryos test showed that Aroclor1254 induced liver degeneration and hypoplasia at the doses of 3.3,6.5,10.0 mg/L.The embryo exhibited part of yolk sac degeneration at 3.3 mg/L,but most degeneration at 6.5,10.0 mg/L.The histological examination showed that the morphological changes such as cell swelling,cytoplasm loose,vacuoles increase and lipid deposition were observed in liver at doses of 2.0,10.0,50 μg/L.The result of real-time quantitative RT-PCR revealed that a significant down-regulation of mRNA vtg gene expression in female zebrafish as compared to the control group,especially at dose of 2.0 μg/L.However,the mRNA vtg gene expression in the male zebrafish was significantly higher than that in the control group at dose of 2.0μg/L.
Conclusion Aroclor1254 has toxic effects on zebrafish and its embryo.Liver could be one of the most important toxic target organs.