Vitellogenin-like gene expression in liver of male zebrafish (Danio rerio) by 1 μM 3-methylcholanthrene treatment: the possibility of a rapid and sensitive in vivo bioassay

This paper describes the possibility of a rapid and sensitive in vivo bioassay for assessing the endocrine-disrupting potential of effluent from wastewater treatment plants. The bioassay uses vitellogenin (Vg)-like gene expression in the liver of male zebrafish (Danio rerio). Adult male zebrafish were exposed to either 1 μM carcinogenic 3-methylcholanthrene (3-MC) or 1 μM 17 β-estradiol (E2) at 25°C for 48 h. The amplification of Vg-like mRNA by reverse transcriptase (RT) polymerase chain reaction (PCR) was then examined by using a newly designed primer pair and the total RNA extracted from the liver of the zebrafish. The results showed that 3-MC could induce vitellogenesis, as could E2. This suggests that this procedure is applicable as a rapid and sensitive in vivo bioassay. It also suggests that carcinogenic compounds such as 3-MC can disrupt the endocrine system.