The zebrafish gill model: Induction of CYP1A, EROD and PAH adduct formation

摘要: Zebrafish (Danio rerio) is a common model species in fish toxicology, and the zebrafish gill potentially useful screening waterborne pollutants. We have previously developed gill-based ethoxyresorufin-O-deethylase (EROD) assay, proposed EROD activity as biomarker for exposure to aryl hydrocarbon receptor (AHR) agonists. In this study we modified assay use zebrafish. used immunohistochemistry localize CYP1A induction, microautoradiography irreversible binding of prototypic polycyclic aromatic hydrocarbon, 7,12-dimethylbenz[a]anthracene (DMBA) gills. Gill filament liver microsomal activities were measured after rainbow trout benzo[a]pyrene (BaP) or beta-naphthoflavone (betaNF). The results showed considerably lower relative induction by betaNF (1microM) than trout, both gills (13-fold versus 230-fold compared control) (5-fold 320-fold control). induced hepatic was similar two species, whereas basal higher trout. gills, enhanced DMBA adduct formation immunostaining. Ellipticine blocked following but had no effect on A notable finding that localization adducts differed from protein betaNF-induced fish; immunoreactivity evenly distributed adduction confined leading edges filaments rakers, i.e., structures being highly exposed DMBA-containing inhaled water. show method suitable determination zebrafish, although seems more sensitive. They also imply sites are markedly influenced kinetic factors.