title: Uterotrophic and Hershberger assays for n-butylbenzene in rats.
abstract: We performed the uterotrophic and Hershberger assays proposed by the OECD to investigate the estrogenic and androgenic effects of n-butylbenzene (nBB). For the uterotrophic assay, nBB was injected subcutaneously at doses of 0, 40, 200, 1000 and 2000 mg/kg to 19-day-old rats for 3 days. In some rats, ethynylestradiol (EE) was also injected subcutaneously at a dose of 0.6 microg/kg after the administration of nBB. There were essentially no differences in the uterine wet or blotted weights between the control and any of the nBB-treated groups, or between the control and any of the nBB plus EE-treated groups. For the Hershberger assay, nBB was administered orally at doses of 0, 200 and 600 mg/kg to 56-day-old castrated rats for 10 days. In some rats, 0.4 mg/kg testosterone propionate (TP) was also administered by subcutaneous injection after the administration of nBB. Doses of 0, 200 and 600 mg/kg nBB were also administered orally to non-castrated rats. The weights of the accessory sex organs of the castrated rats showed no significant differences between the control and any of the nBB-treated groups or between the control and the nBB plus TP-treated groups. No significant differences in the weights of the accessory sex organs of the non-castrated rats were observed between the control and the nBB-treated groups. These findings suggest that nBB does not have any endocrine-disrupting properties on in vivo screening tests.
authors.affiliation: Chemicals Assessment Center, Chemicals Evaluation and Research Institute, Hita, Oita, Japan. yamasaki-kanji@ceri.jp
authors.forename: Kanji
authors.initials: K
authors.lastname: Yamasaki
authors.forename: Masakuni
authors.initials: M
authors.lastname: Sawaki
authors.forename: Shuji
authors.initials: S
authors.lastname: Noda
authors.forename: Mineo
authors.initials: M
authors.lastname: Takatsuki
mesh_terms: D000284:Administration, Oral; D000726:Androgen Antagonists / Q000008:administration & dosage / Q000633:toxicity*; D000818:Animals; D001555:Benzene Derivatives / Q000008:administration & dosage / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004965:Estrogen Antagonists / Q000008:administration & dosage / Q000633:toxicity*; D004997:Ethinyl Estradiol / Q000633:toxicity; D005260:Female; D007279:Injections, Subcutaneous; D009929:Organ Size / Q000187:drug effects; D010052:Ovariectomy; D051381:Rats; D011919:Rats, Inbred Strains; D013739:Testosterone / Q000633:toxicity; D018675:Toxicity Tests; D014599:Uterus / Q000187:drug effects / Q000473:pathology
chemical_list: D000726:Androgen Antagonists; D001555:Benzene Derivatives; D004965:Estrogen Antagonists; D013739:Testosterone; D004997:Ethinyl Estradiol; C053761:n-butylbenzene