Establishment of a short-term, in vivo screening method for detecting chemicals with juvenile hormone activity using adult Daphnia magna.
Juvenile hormone (JH) and JH agonists have been shown to induce male offspring production in various daphnids, including Daphnia magna using OECD TG211. The critical period (about 1h) for JH action on ova in the parent's ovary to induce male offspring is existing at 7-8h later from ovulation. Therefore, we considered that adult D. magna could be used to produce a short-term screening method for detecting JH analogs. Using this method, we successfully demonstrated male offspring induction in the second broods after exposure to JH or JH agonists. After investigating the exposure time, the number of repetitions and the exposure concentration, we established a short-term, in vivo screening method for detecting JH analogs using adult D. magna. We examined positive and negative control chemicals using a previously developed method and verified the validity of our new testing method.
Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8561, Japan.
Ryoko
R
Abe
Haruna
H
Watanabe
Masumi
M
Yamamuro
Taisen
T
Iguchi
Norihisa
N
Tatarazako
D000818:Animals; D003621:Daphnia / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D052244:Endocrine Disruptors / Q000633:toxicity*; D023381:Endpoint Determination; D005260:Female; D007605:Juvenile Hormones / Q000819:agonists*; D008297:Male; D009865:Oocytes / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012744:Sex Ratio; D013997:Time Factors; D018675:Toxicity Tests / Q000379:methods*
D052244:Endocrine Disruptors; D007605:Juvenile Hormones
Daphnia magna; OECD TG211; juvenile hormone-like activity; sex ratio; short-term screening (STS) method