title: Effects of eutrophication on vitellogenin gene expression in male fathead minnows (Pimephales promelas) exposed to 17alpha-ethynylestradiol in field mesocosms.
abstract: This study evaluated the effect of aquatic secondary nutrient supply levels (nitrogen and phosphorus) on the subcellular response of adult male fathead minnows (Pimephales promelas) exposed to a single nominal concentration of 17alpha-ethynylestradiol (EE2), a potent synthetic estrogen, under quasi-natural field conditions. Outdoor mesocosms were maintained under low, medium, and high nutrient supply conditions as categorized by total phosphorus (TP) level (nominal 0.012, 0.025, and 0.045 mg TP/L, respectively), and treated with EE2 with and without a carrier solvent. Using reverse transcription-polymerase chain reaction methods, vitellogenin gene (Vg) expression was determined in the fish collected at 0 h, 8 h, 24 h, 4 d, 7 d, and 14 d post-exposure. Induction of Vg was detected as early as 8h post-exposure, with and without the carrier solvent, and persisted through Day 14. Results showed Vg to be significantly greater at low nutrient levels (p<0.05), suggesting that EE2 bioavailability to the fish was likely greater under less-turbid water conditions.
authors.affiliation: Molecular Indicators Research Branch, Ecological Exposure Research Division, National Exposure Research Laboratory, Office of Research and Development, United States Environmental Protection Agency, Cincinnati, OH 45268, USA.
authors.forename: Denise A
authors.initials: DA
authors.lastname: Gordon
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Toth
authors.forename: David W
authors.initials: DW
authors.lastname: Graham
authors.forename: James M
authors.initials: JM
authors.lastname: Lazorchak
authors.forename: Tirumuru V
authors.initials: TV
authors.lastname: Reddy
authors.forename: Charles W
authors.initials: CW
authors.lastname: Knapp
authors.forename: Frank
authors.initials: F
authors.lastname: deNoyelles
authors.forename: Scott
authors.initials: S
authors.lastname: Campbell
authors.forename: David L
authors.initials: DL
authors.lastname: Lattier
mesh_terms: D000818:Animals; D003530:Cyprinidae / Q000378:metabolism*; D017753:Ecosystem; D052244:Endocrine Disruptors / Q000633:toxicity*; D004997:Ethinyl Estradiol / Q000633:toxicity*; D005068:Eutrophication; D005308:Fertilizers; D015870:Gene Expression; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018675:Toxicity Tests; D014819:Vitellogenins / Q000235:genetics*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D052244:Endocrine Disruptors; D005308:Fertilizers; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D004997:Ethinyl Estradiol; D009584:Nitrogen