Effects of eutrophication on vitellogenin gene expression in male fathead minnows (Pimephales promelas) exposed to 17alpha-ethynylestradiol in field mesocosms.
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.
Gordon
Denise A
DA
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.
Toth
Gregory P
GP
Graham
David W
DW
Lazorchak
James M
JM
Reddy
Tirumuru V
TV
Knapp
Charles W
CW
deNoyelles
Frank
F
Campbell
Scott
S
Lattier
David L
DL
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*
D052244:Endocrine Disruptors; D005308:Fertilizers; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D004997:Ethinyl Estradiol; D009584:Nitrogen