title: Effect of prenatal exposure to bisphenol A on the serum testosterone concentration of rats at birth.
abstract: In the rat, testosterone (T) in the neonatal period plays an important role in sexual differentiation and there is a serum T surge in male rats 2 hours after birth. Pregnant female rats were exposed to various doses of bisphenol A (BPA) from gestational day 1 (GD1) through 2 hours after parturition. About half of the BPA-exposed and control dams were subjected to cesarean section on GD22. The male fetuses on GD22 were immediately sacrificed and blood was collected. The other half of the BPA-treated and control dams delivered at GD23 (parturition day). The male pups were sacrificed 2 hours after birth. Serum T concentration was determined by radioimmunoassay (RIA). The BPA concentration in the fetal serum on GD22 increased inversely to the T levels in the serum. The T concentration in the pups' serum 2 hours after birth decreased inversely to the BPA concentration in the serum. However, there were no differences in the serum T concentration among the various doses of BPA. These results suggest that exposure to BPA in utero inhibits the T surge in the neonatal period and we speculate that exposure to BPA in utero disrupts the endocrine environment in the neonatal male.
authors.affiliation: Institute of Experimental Animals, St Marianna University Graduate School of Medicine, Kawasaki, Kanagawa, Japan. m3tanaka@marianna-u.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Nakaya
authors.forename: M
authors.initials: M
authors.lastname: Katayama
authors.forename: H
authors.initials: H
authors.lastname: Leffers
authors.forename: S
authors.initials: S
authors.lastname: Nozawa
authors.forename: R
authors.initials: R
authors.lastname: Nakazawa
authors.forename: T
authors.initials: T
authors.lastname: Iwamoto
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001559:Benzhydryl Compounds; D004305:Dose-Response Relationship, Drug; D004968:Estrogens, Non-Steroidal / Q000097:blood / Q000633:toxicity*; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D005865:Gestational Age; D008297:Male; D018811:Maternal Exposure; D008431:Maternal-Fetal Exchange; D010636:Phenols / Q000097:blood / Q000633:toxicity*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D012733:Sex Differentiation / Q000187:drug effects; D013739:Testosterone / Q000097:blood*; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D004968:Estrogens, Non-Steroidal; D010636:Phenols; D013739:Testosterone; C006780:bisphenol A; D000098826:Bisphenol A Compounds