title: Placental development during early pregnancy in sheep: estrogen and progesterone receptor messenger RNA expression in pregnancies derived from in vivo-produced and in vitro-produced embryos.
abstract: Sex steroids are important regulators of angiogenesis and growth in reproductive tissues, including the placenta. In experiment (exp.) 1, to examine the expression of a suite of sex steroid receptors throughout early pregnancy, maternal (caruncular [CAR]) and fetal (fetal membranes [FM]) placental tissues were collected on days 14 to 30 after mating and on day 10 after estrus (nonpregnant controls). In exp. 2, to examine the hypothesis that assisted reproductive technology would affect the expression of the same suite of sex steroid receptors, pregnancies were achieved through natural mating (NAT) or transfer of embryos from natural mating (NAT-ET), in vitro fertilization (IVF), or in vitro activation (IVA), and CAR and FM were collected on day 22. In exp. 1, for CAR messenger RNA (mRNA) expression of estrogen receptors (ESR) 1 and 2, nuclear (n) progesterone receptors (PGR) and membrane (m) PGRα, β, and γ were affected (P < 0.02) by pregnancy stage, as were ESR1, nPGR, and mPGRα, β, and γ for FM (P < 0.03). In exp. 2, for CAR, mRNA expression of ESR1 and nPGR was decreased (P < 0.001) in NAT-ET, IVF, and IVA groups compared with NAT. For FM, mRNA expression of ESR1 tended to be greater (P = 0.10) in the IVA group compared with NAT and NAT-ET, and GPER1 was greater (P < 0.05) in NAT-ET and IVF compared with NAT. These data establish the normal pattern of sex steroid receptor mRNA expression in maternal and fetal placenta during early pregnancy in sheep, and in addition, suggest that altered expression of placental sex steroid receptors may be an early event leading to poor placental vascularization and growth after assisted reproductive technology.
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, ND 58108, USA. Electronic address: Larry.Reynolds@ndsu.edu.
authors.forename: L P
authors.initials: LP
authors.lastname: Reynolds
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Haring
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Johnson
authors.affiliation: Department of Animal and Range Sciences, New Mexico State University, Las Cruces, NM, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Ashley
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Redmer
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: P P
authors.initials: PP
authors.lastname: Borowicz
authors.affiliation: Department of Animal Sciences, North Dakota State University, Fargo, ND 58108, USA; Center for Nutrition and Pregnancy, North Dakota State University, Fargo, ND 58108, USA.
authors.forename: A T
authors.initials: AT
authors.lastname: Grazul-Bilska
mesh_terms: D000818:Animals; D004624:Embryo Transfer / Q000662:veterinary*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D010929:Placentation / Q000502:physiology*; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000235:genetics / Q000378:metabolism*; D012756:Sheep / Q000502:physiology*; D014599:Uterus / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone
keywords: Assisted reproductive technology; Early pregnancy; Placenta; Sex steroid receptor; Sheep