Kinetics of vitellogenin protein and mRNA induction and depuration in fish following laboratory and environmental exposure to oestrogens.
Plaice, flounder and sand goby were exposed to ethynylestradiol (EE2) for 21 days and then followed for up to 31 days after removal of the oestrogen. Plasma vitellogenin (VTG) and hepatic VTG mRNA were determined in groups of fish sampled during the induction and post-exposure phases. VTG mRNA increased slightly earlier than plasma protein, but both reached maxima by 21 days. In contrast, VTG mRNA decayed much more rapidly than protein after EE2 exposure was terminated (typical values t(1/2) mRNA 3 days, protein 15-30 days). Vitellogenin and VTG mRNA thus measure different temporal events and this is illustrated by field data of male flounder in which both parameters have been determined. Few fish show co-ordinate increased VTG mRNA and vitellogenin but rather more fish have increased vitellogenin. Low level increases of VTG mRNA (5 X) is observed in some fish without increased vitellogenin and this may represent polymorphic differences between individual fish.
Craft
John A
JA
School of Biological and Biomedical Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow G4 0BA, Scotland, UK. j.a.craft@gcal.ac.uk
Brown
Margaret
M
Dempsey
Kate
K
Francey
Jill
J
Kirby
Mark F
MF
Scott
Alexander P
AP
Katsiadaki
Ioanna
I
Robinson
Craig D
CD
Davies
Ian M
IM
Bradac
Philippe
P
Moffat
Colin F
CF
D000818:Animals; D004781:Environmental Exposure; D004997:Ethinyl Estradiol / Q000494:pharmacology*; D005399:Fishes / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D007668:Kidney / Q000378:metabolism; D007700:Kinetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D006113:United Kingdom; D014819:Vitellogenins / Q000097:blood* / Q000235:genetics
D012333:RNA, Messenger; D014819:Vitellogenins; D004997:Ethinyl Estradiol