title: Sustained high temperature increases the vitellogenin response to 17α-ethynylestradiol in mummichog (Fundulus heteroclitus).
abstract: Mummichog (Fundulus heteroclitus), an estuarine fish of the western Atlantic, were acclimated to three salinities (0, 16 or 32 ppt) or three temperatures (10, 20 or 26 °C) and exposed to nominal 50 or 250 ng/L 17α-ethynylestradiol (EE2) for 14 days. In a separate experiment, fish were exposed to the same levels of EE2 and were subjected to a 1h heat shock (20-30 °C) on the 14th day and allowed to recover for 20 h. We were interested in whether or not susceptibility to EE2 exposure, as indicated by increases in vitellogenin (vtg) gene expression would change with high and low salinity, warm or cold temperature acclimation or acute heat shock. We also investigated the potential role of heat shock proteins (HSPs) under these conditions. Liver vtg1 mRNA was significantly induced in male mummichog exposed to 50 and 250 ng/L EE2, but salinity acclimation or acute heat shock did not further affect this induction. Males acclimated to 26 °C and exposed to 250 ng/L EE2 induced 3.5-fold more vtg1 mRNA than EE2 exposed males acclimated to 10 °C. HSP90 and HSP70 protein were largely unaffected by EE2 exposure. Our findings suggest that mummichog are more susceptible to EE2 under sustained temperature increases that may occur seasonally or with warming of coastal waters.
authors.affiliation: Department of Biology, Mount Allison University, Sackville, NB E4L 1G7, Canada.
authors.forename: Kavish
authors.initials: K
authors.lastname: Chandra
authors.affiliation: Department of Natural Resources and the Environment, Center for Environmental Sciences and Engineering, University of Connecticut, Storrs, CT, 06269-4087, USA.
authors.forename: Thijs
authors.initials: T
authors.lastname: Bosker
authors.affiliation: Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, S7N 5A8, Canada.
authors.forename: Natacha
authors.initials: N
authors.lastname: Hogan
authors.affiliation: Department of Biology and Canadian Rivers Institute, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lister
authors.affiliation: Department of Biology and Canadian Rivers Institute, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada.
authors.forename: Deborah
authors.initials: D
authors.lastname: MacLatchy
authors.affiliation: Department of Biology, Mount Allison University, Sackville, NB E4L 1G7, Canada. Electronic address: scurrie@mta.ca.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Currie
mesh_terms: D000818:Animals; D004997:Ethinyl Estradiol / Q000633:toxicity*; D005260:Female; D023781:Fundulidae / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D018869:Heat-Shock Response / Q000187:drug effects; D006358:Hot Temperature; D015151:Immunoblotting; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D011897:Random Allocation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D054712:Salinity; D014819:Vitellogenins / Q000235:genetics / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins; D012333:RNA, Messenger; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D004997:Ethinyl Estradiol