title: Responses and recovery pattern of sex steroid hormones in testis of Nile tilapia (Oreochromis niloticus) exposed to sublethal concentration of methomyl.
abstract: Tilapia were exposed to sublethal methomyl concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 days, and then transferred to methomyl-free water for 18 days. The sexual steroid hormones 17β-estradiol (E2), testosterone (T), and 11-ketotestosterone (11-KT) in tilapia testes were examined at 0, 6, 12, 18, 24 and 30 days after methomyl exposure, and at 18 days after fish were transferred to methomyl-free water. There were no significant changes in the hormone parameters in testes of tilapia exposed to low concentration 0.2 and 2 μg/L methomyl compared with the controls. However, high concentration 20 and 200 μg/L methomyl had the potential to disrupt the endocrine system of male tilapia, as shown by an increase in E2and a decrease in T and 11-KT in the testes. Thus, it would appear that the 2 μg/L methomyl might be considered the no-observed-adverse-effect level. Recovery data showed that the effects produced by the lower concentration of 20 μg/L were reversible but the effects were not reversible at the higher concentration of 200 μg/L.
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Shun Long
authors.initials: SL
authors.lastname: Meng
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Li Ping
authors.initials: LP
authors.lastname: Qiu
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Geng Dong
authors.initials: GD
authors.lastname: Hu
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Li Min
authors.initials: LM
authors.lastname: Fan
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Song
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Jian Hong
authors.initials: JH
authors.lastname: Qu
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China.
authors.forename: Dan Dan
authors.initials: DD
authors.lastname: Li
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China. chenjz@ffrc.cn.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China. chenjz@ffrc.cn.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China. chenjz@ffrc.cn.
authors.forename: Jia Zhang
authors.initials: JZ
authors.lastname: Chen
authors.affiliation: Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, 214081, P.R. China. xup@ffrc.cn.|Laboratory of Quality & Safety Risk Assessment for Aquatic Products on Environmental Factors, Ministry of Agriculture, Wuxi, 214081, P.R. China. xup@ffrc.cn.|Key Laboratory of Fishery Eco-environment Assessment and Resource Conservation in Middle and Lower Reaches of the Yangtze River, CAFS, Wuxi, 214081, P.R. China. xup@ffrc.cn.
authors.forename: Pao
authors.initials: P
authors.lastname: Xu
mesh_terms: D000818:Animals; D023681:Cichlids / Q000502:physiology*; D004958:Estradiol / Q000378:metabolism; D005260:Female; D012739:Gonadal Steroid Hormones / Q000378:metabolism*; D008297:Male; D008724:Methomyl / Q000378:metabolism / Q000633:toxicity*; D019055:No-Observed-Adverse-Effect Level; D013737:Testis / Q000187:drug effects* / Q000378:metabolism; D013739:Testosterone / Q000031:analogs & derivatives; D059551:Toxicity Tests, Subacute; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity*
chemical_list: D012739:Gonadal Steroid Hormones; D014874:Water Pollutants, Chemical; D008724:Methomyl; D013739:Testosterone; D004958:Estradiol; C003600:11-ketotestosterone
keywords: Methomyl; Recovery pattern; Sex steroid hormone; Testis; Tilapia