title: Induction of uterine calbindin-D9k through an estrogen receptor-dependent pathway following single injection with xenobiotic agents in immature rats.
abstract: Various environmental chemicals, both natural and synthetic, are believed to act as endocrine disruptors (EDs) in mammals. In this study, a new in vivo model of immature rats was used to explore the induction of calbindin-D9k (CaBP-9k) following a single injection of EDs. In a time-dependent experiment, immature rats at postnatal day 16 were treated with high doses (600 mg/kg body weight [BW]) of 4-tert-octyphenol (OP), p-nonylphenol (NP), or bisphenol A (BPA), and euthanized at different time points (3, 6, 12, 24, or 48 h). For a dose-dependent study, immature rats were given different doses (200, 400, or 600 mg/kg BW) and euthanized at 24 h after injection. After treatment with these EDs, the effects on CaBP-9k mRNA and protein were examined by Northern and Western blot analyses, respectively. An anti-estrogen, ICI 182,780, was employed to examine the potential involvement of estrogen receptor (ER) in the induction of estrogen receptor-mediated physiologic responses in vivo. A single treatment with each of the chemicals, at 600 mg/kg BW, resulted in a significant increase in the expression of CaBP-9k mRNA and protein 24 h after injection. In addition, treatment with OP, NP, or BPA resulted in a positive uterotrophic response. Cotreatment with the ER antagonist ICI 182,780 completely prevented the ED-induced uterine weight gain. Taken together, these results demonstrate that a single injection of OP, NP, or BPA results in an increase of CaBP-9k mRNA and protein via an ER-dependent pathway in the uterus of immature rats. This new model may be important to elucidate the mechanism of action of xenoestrogens on estrogen-sensitive tissue.
authors: Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk, Republic of Korea.
authors: Vu Hoang
authors: VH
authors: Dang
authors: Kyung-Chul
authors: KC
authors: Choi
authors: Sang-Hwan
authors: SH
authors: Hyun
authors: Eui-Bae
authors: EB
authors: Jeung
mesh_terms: D000818:Animals; D001559:Benzhydryl Compounds; D064026:Calbindins; D052244:Endocrine Disruptors / Q000633:toxicity; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D004965:Estrogen Antagonists / Q000494:pharmacology; D004968:Estrogens, Non-Steroidal / Q000633:toxicity; D005260:Female; D000077267:Fulvestrant; D007279:Injections, Subcutaneous; D009929:Organ Size / Q000187:drug effects; D010636:Phenols / Q000633:toxicity*; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000037:antagonists & inhibitors / Q000378:metabolism; D064030:S100 Calcium Binding Protein G / Q000096:biosynthesis* / Q000235:genetics; D014599:Uterus / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D015262:Xenobiotics / Q000633:toxicity; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D064026:Calbindins; D052244:Endocrine Disruptors; D004958:Estradiol; D004965:Estrogen Antagonists; D004968:Estrogens, Non-Steroidal; D000077267:Fulvestrant; D010636:Phenols; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D064030:S100 Calcium Binding Protein G; D015262:Xenobiotics; C576508:S100g protein, rat; C025256:nonylphenol; C105260:4-tert-octylphenol; C006780:bisphenol A; D000098826:Bisphenol A Compounds