title: Histopathological characteristics of luteal hypertrophy induced by ethylene glycol monomethyl ether with a comparison to normal luteal morphology in rats.
abstract: Ethylene glycol monomethyl ether (EGME) is a known reproductive toxicant that induces luteal hypertrophy in rat ovaries. In this study, we characterized the histopathological features of corpora lutea (CL) from EGME-treated rats and compared them with normal CL formation and regression. Normally cycling female Sprague-Dawley rats were treated with 5-bromo-2'-deoxyuridine (BrdU) intraperitoneally on the morning of estrus and their ovaries were examined 1 (metestrus), 4 (estrus), 8 (estrus), or 12 (estrus) days later to observe the transition of BrdU-labeled cells within in the CL. CL at each time point of estrus stage were classified into 4 types: Type I (newly formed CL), Type II (mature CL), Type III (regressing CL), and Type IV (residual CL). CL almost fully regressed within 4 estrus cycles. In contrast, in female rats given EGME orally (30, 100, or 300 mg/kg for 2 or 4 weeks), luteal cells were hypertrophic with abundant cytoplasm. Although the size of CL varied, all CL in EGME-treated rats had histological features similar to Type II CL, but they were more hypertrophic with less apoptosis. These results suggest that EGME has a luteal hypertrophic effect on all CL phases, including regression.
authors.affiliation: Tsukuba, Drug Safety Japan, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Ibaraki, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Taketa
authors.forename: Akira
authors.initials: A
authors.lastname: Inomata
authors.forename: Satoru
authors.initials: S
authors.lastname: Hosokawa
authors.forename: Jiro
authors.initials: J
authors.lastname: Sonoda
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hayakawa
authors.forename: Kyoko
authors.initials: K
authors.lastname: Nakano
authors.forename: Yuki
authors.initials: Y
authors.lastname: Momozawa
authors.forename: Joji
authors.initials: J
authors.lastname: Yamate
authors.forename: Midori
authors.initials: M
authors.lastname: Yoshida
authors.forename: Toyohiko
authors.initials: T
authors.lastname: Aoki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsukidate
mesh_terms: D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D004971:Estrus / Q000187:drug effects; D005026:Ethylene Glycols / Q000633:toxicity*; D005260:Female; D006984:Hypertrophy / Q000139:chemically induced / Q000473:pathology; D008184:Luteal Cells / Q000187:drug effects / Q000473:pathology*; D003341:Luteolysis / Q000187:drug effects*; D023421:Models, Animal; D010053:Ovary / Q000187:drug effects / Q000473:pathology; D011374:Progesterone / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D005026:Ethylene Glycols; D011374:Progesterone; C005219:methyl cellosolve; D001973:Bromodeoxyuridine