title: Progesterone and estradiol in cat placenta--biosynthesis and tissue concentration.
abstract: Ovarian and placental steroids are essential for the maintenance of pregnancy. In some mammals it is evident that the placenta is responsible for the production of steroids. However, in the domestic cat, steroid secretion from the placenta has not yet been elucidated. Our study aimed to find out whether feline placentae are able to produce steroids. Placentae from different pregnancy stages were analyzed for mRNA expression of five steroidogenic enzymes (HSD3B1, CYP11A1, CYP17A1, HSD17B1 and CYP19A1) and for tissue concentrations of progesterone and estradiol. Steroidogenic enzymes responsible for the final steps of estradiol (CYP19A1) and progesterone synthesis (HSD3B) were expressed at very high levels and followed almost the same pattern over pregnancy as the intraplacental hormones themselves. By contrast, the other enzymes were found in very low quantities suggesting that biosynthesis occurs via extra-placental steroid precursors. The plasma steroid profiles measured by other groups differ from the placental hormone courses determined by us; therefore we conclude that the feline placenta can produce progesterone and estradiol.
authors.affiliation: Leibniz-Institute for Zoo and Wildlife Research, PF601103, 10252 Berlin, Germany. braun@izw-berlin.de
authors.forename: Beate C
authors.initials: BC
authors.lastname: Braun
authors.forename: Lina
authors.initials: L
authors.lastname: Zschockelt
authors.forename: Martin
authors.initials: M
authors.lastname: Dehnhard
authors.forename: Katarina
authors.initials: K
authors.lastname: Jewgenow
mesh_terms: D000818:Animals; D001141:Aromatase / Q000235:genetics; D002415:Cats; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000235:genetics; D004798:Enzymes / Q000235:genetics* / Q000378:metabolism; D004958:Estradiol / Q000096:biosynthesis / Q000378:metabolism*; D004960:Estradiol Dehydrogenases / Q000235:genetics; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D046008:Lynx / Q000235:genetics; D009097:Multienzyme Complexes / Q000235:genetics; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011374:Progesterone / Q000096:biosynthesis / Q000378:metabolism*; D011375:Progesterone Reductase / Q000235:genetics; D013254:Steroid 17-alpha-Hydroxylase / Q000235:genetics; D013251:Steroid Isomerases / Q000235:genetics
chemical_list: C021425:3 beta-hydroxysteroid oxidoreductase-delta(5) 3-ketosteroid isomerase; D004798:Enzymes; D009097:Multienzyme Complexes; D011374:Progesterone; D004958:Estradiol; D011375:Progesterone Reductase; D004960:Estradiol Dehydrogenases; D001141:Aromatase; D013254:Steroid 17-alpha-Hydroxylase; D002786:Cholesterol Side-Chain Cleavage Enzyme; D013251:Steroid Isomerases