title: Cytochrome P450IA mRNA expression in feral Hudson River tomcod.
abstract: We sought to determine if levels of cytochrome P450IA gene expression are environmentally induced in feral populations of Hudson River tomcod, a cancer prone fish, and whether laboratory exposure of tomcod to artificially spiked and naturally contaminated Hudson sediments can elicit a significant response. Using Northern blot analysis, we found levels of P450IA mRNA in tomcod collected from two Hudson River sites higher than those in tomcod from a river in Maine. Depuration of environmentally induced Hudson tomcod P450IA mRNA was rapid, with an initial detectable decline in P450 gene expression by 8 hr and basal levels reached by 5 days. Intraperitoneal injection of beta-napthoflavone in depurated Hudson tomcod resulted in a 15-fold induction of P450 gene expression within 26 hr. Exposure of depurated Hudson tomcod to natural sediment spiked with two PAHs resulted in a 7-fold induction of P450 gene expression. Exposure of depurated tomcod to sediment from a contaminated Hudson site also resulted in a 7- to 15-fold induction of P450IA mRNA expression. Northern blot analysis revealed a second polymorphic cytochrome P450IA mRNA band in some tomcod which was also detected by Southern blot analysis. Induction of cytochrome P450IA mRNA in Atlantic tomcod may provide a sensitive biomarker of environmentally relevant concentrations of some pollutants in the Hudson and other northeastern tidal rivers.
authors.affiliation: New York University Medical Center, Institute of Environmental Medicine, Tuxedo 10987.
authors.forename: G L
authors.initials: GL
authors.lastname: Kreamer
authors.forename: K
authors.initials: K
authors.lastname: Squibb
authors.forename: D
authors.initials: D
authors.lastname: Gioeli
authors.forename: S J
authors.initials: SJ
authors.lastname: Garte
authors.forename: I
authors.initials: I
authors.lastname: Wirgin
mesh_terms: D000818:Animals; D000835:Animals, Wild; D001571:Benzoflavones / Q000494:pharmacology; D015152:Blotting, Northern; D015139:Blotting, Southern; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D004247:DNA / Q000032:analysis; D004790:Enzyme Induction / Q000187:drug effects; D005399:Fishes / Q000235:genetics*; D005618:Fresh Water; D015971:Gene Expression Regulation, Enzymologic; D008281:Maine; D009518:New York; D012333:RNA, Messenger / Q000096:biosynthesis*; D015183:Restriction Mapping; D014876:Water Pollution / Q000009:adverse effects*; D019324:beta-Naphthoflavone; D010130:p-Aminohippuric Acid / Q000494:pharmacology
chemical_list: D001571:Benzoflavones; D012333:RNA, Messenger; D019324:beta-Naphthoflavone; D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D010130:p-Aminohippuric Acid