title: [Study on reproductive and developmental toxicity of the pregnant mice and their foetus co-administered by p, p'-DDE and beta-BHC].
abstract: OBJECTIVE
  To explore effects of p, p'-DDE and beta-BHC on reproduction and development in mice.
  
  
  METHODS
  The pregnant Kunming SPF mice of 12 to 14 days were co-administered by oral gavage for 3 days at different concentrations of 0, 1, 5 and 10 mg/kg bw of p, p'-DDE and beta-BHC. The concentrations of estradiol (E2) and progesterone (P) in sera of the dosed mice were determined by the Serozyme kits (Bio-Ekon biotechnology Co., Beijing, China), following the procedures described by the manufacturer. RT-PCR was employed to detect abundant expression of alpha-estrogen receptor (alpha-ER) gonadtropin releasing hormone (GnRH) and beta-endorphin (beta-EP) mRNA in placentae.
  
  
  RESULTS
  (1) Reproductive effects: with increase of the administered p,p'-DDE and P-BHC,the organ coefficient of uterus and its intraluminal fluid increased, the unterine nidation quantity decreased, the anogenital distance (AGD) and ratio of female to male raised, the concentration of estradiol and progesterone in sera of the dosed mice went up, and the abundant expression of alpha-ER and GnRH mRNA rised while beta-EP dropped in placentae in a dose-dependant manner. Significant difference of these indexes were found between the treat groups and control (P < 0.05). (2) Developmental effects: with increase of the administered p,p'-DDE and beta-BHC, the gained weights of pregnant mice reduced, organ coefficient of liver increased,the quantity of live foetus decreased, the times of adverse pregnancy outcome went up, and the percent of female foetus increased. They all presented a dose-effect relation and significance of difference (P < 0.05).
  
  
  CONCLUSIONS
  p, p'-DDE and beta-BHC disrupt reproductive function, thereby result in dysreproduction and maldevelopment, and unbalance of ratio of female to male.
authors.affiliation: School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Guo-hong
authors.initials: GH
authors.lastname: Liu
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Ke-di
authors.initials: KD
authors.lastname: Yang
authors.forename: Shao-xiong
authors.initials: SX
authors.lastname: Mo
mesh_terms: D000818:Animals; D003633:Dichlorodiphenyl Dichloroethylene / Q000633:toxicity*; D004357:Drug Synergism; D005260:Female; D005333:Fetus; D007987:Gonadotropin-Releasing Hormone / Q000187:drug effects / Q000378:metabolism; D001556:Hexachlorocyclohexane / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity; D018811:Maternal Exposure / Q000009:adverse effects*; D051379:Mice; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced* / Q000503:physiopathology; D011960:Receptors, Estrogen / Q000187:drug effects / Q000378:metabolism; D012098:Reproduction / Q000187:drug effects*
chemical_list: D007306:Insecticides; D011960:Receptors, Estrogen; D007987:Gonadotropin-Releasing Hormone; D003633:Dichlorodiphenyl Dichloroethylene; D001556:Hexachlorocyclohexane