title: Evaluation of an in utero through lactational exposure protocol for detection of estrogenic effects of ethinyl estradiol on the offspring of rats: preliminary trial.
abstract: As a preliminary trial of an in utero through lactational exposure protocol, ethinyl estradiol, 0, 0.5, 5, or 50 micro g/kg/day, was administered by gavage to pregnant Crj: CD (SD) IGS BR rats from gestational day (GD) 7 to day 18 after delivery to evaluate the efficacy of this protocol and to estimate optimal endpoints. The dams showed no abnormalities. Cleft phallus was observed in female offspring at 50 micro g/kg. Other than a retardation of body weight gain in both sexes at 50 micro g/kg/day, no other abnormal findings were detected. The fact that cleft phallus was the only change induced suggests that the protocol is applicable to the detection of effects of estrogenic chemicals given to pregnant rats on offspring development and that the morphology of the female external genitalia may be a useful endpoint.
authors.affiliation: Chemicals Evaluation and Research Institute, 3-822, Ishii-machi, Hita, Oita 877-0061, Japan. sawaki-masakuni@cerij.jp
authors.forename: Masakuni
authors.initials: M
authors.lastname: Sawaki
authors.forename: Shuji
authors.initials: S
authors.lastname: Noda
authors.forename: Takako
authors.initials: T
authors.lastname: Muroi
authors.forename: Hideo
authors.initials: H
authors.lastname: Mitoma
authors.forename: Saori
authors.initials: S
authors.lastname: Takakura
authors.forename: Satoko
authors.initials: S
authors.lastname: Sakamoto
authors.forename: Kanji
authors.initials: K
authors.lastname: Yamasaki
mesh_terms: D000014:Abnormalities, Drug-Induced; D000284:Administration, Oral; D000818:Animals; D000831:Animals, Newborn; D002972:Cleft Palate / Q000139:chemically induced; D004305:Dose-Response Relationship, Drug; D023381:Endpoint Determination / Q000379:methods; D004967:Estrogens / Q000633:toxicity*; D004997:Ethinyl Estradiol / Q000633:toxicity*; D005260:Female; D005836:Genitalia, Female / Q000002:abnormalities; D007774:Lactation; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004967:Estrogens; D004997:Ethinyl Estradiol