title: Expression of mouse 17beta-hydroxysteroid dehydrogenase/17-ketosteroid reductase type 7 in the ovary, uterus, and placenta: localization from implantation to late pregnancy.
abstract: Rodent 17beta-hydroxysteroid dehydrogenase/17-ketosteroid reductase type 7 (17HSD/KSR7) catalyzes the conversion of estrone (E1) to estradiol (E2) and is abundantly expressed in the ovaries of pregnant animals in particular. In the present work we demonstrate cell-specific expression of 17HSD/KSR7 in the ovaries, uteri, and placentas of pregnant and nonpregnant mice using in situ hybridization. The results show that mouse 17HSD/KSR7 (m17HSD/KSR7) messenger RNA is distinctly and exclusively expressed in a proportion of corpora lutea (CLs). During pregnancy, expression of m17HSD/KSR7 is most abundant around embryonic day 14.5 (E14.5), when the ovaries are filled with CLs expressing 17HSD/KSR7. In the uterus, m17HSD/KSR7 is first detected on E5.5, when expression surrounds the implantation site on the antimesometrial side. As gestation progresses, m17HSD/KSR7 is expressed in the decidua capsularis on E8 and E9.5, disappearing thereafter from the antimesometrial decidua. On E9 onward, m17HSD/KSR7 messenger RNA expression takes place at the junctional zone of the developing placenta. On E12.5 and E14.5, m17HSD/KSR7 is abundantly expressed in the spongiotrophoblasts, where expression gradually declines toward parturition. In conclusion, m17HSD/KSR7 expression in the CL is related to the life span of the CL. Moreover, spatial and temporal expression of m17HSD/KSR7 in the uterus suggests that locally produced E2 plays a role in implantation and/or decidualization. Finally, the results indicate that mouse placenta is capable of converting E1 to E2 in situ, and that the synthesized E2 may be effective in a paracrine, autocrine, and/or intracrine manner and be involved in placentation.
authors.affiliation: Biocenter Oulu and World Health Organization Collaborating Center for Research on Reproductive Health, University of Oulu, Finland.
authors.forename: P
authors.initials: P
authors.lastname: Nokelainen
authors.forename: H
authors.initials: H
authors.lastname: Peltoketo
authors.forename: M
authors.initials: M
authors.lastname: Mustonen
authors.forename: P
authors.initials: P
authors.lastname: Vihko
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000235:genetics*; D000818:Animals; D003001:Cloning, Molecular; D003338:Corpus Luteum / Q000201:enzymology; D003656:Decidua / Q000201:enzymology; D010064:Embryo Implantation / Q000502:physiology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D005865:Gestational Age; D017403:In Situ Hybridization; D051379:Mice; D008815:Mice, Inbred Strains; D010053:Ovary / Q000201:enzymology* / Q000502:physiology; D010920:Placenta / Q000201:enzymology* / Q000502:physiology; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D014599:Uterus / Q000201:enzymology* / Q000502:physiology
chemical_list: D012333:RNA, Messenger; D015067:17-Hydroxysteroid Dehydrogenases