title: An aldose reductase with 20 alpha-hydroxysteroid dehydrogenase activity is most likely the enzyme responsible for the production of prostaglandin f2 alpha in the bovine endometrium.
abstract: Prostaglandins are important regulators of reproductive function. In particular, prostaglandin F2 alpha (PGF(2 alpha)) is involved in labor and is the functional mediator of luteolysis to initiate a new estrous cycle in many species. These actions have been extensively studied in ruminants, but the enzymes involved are not clearly identified. Our objective was to identify which prostaglandin F synthase is involved and to study its regulation in the endometrium and in endometrial primary cell cultures. The expression of all previously known prostaglandin F synthases (PGFSs), two newly discovered PGFS-like genes, and a 20 alpha-hydroxysteroid dehydrogenase was studied by Northern blot and reverse transcription PCR. These analyses revealed that none of the known PGFS or the PGFS-like genes were significantly expressed in the endometrium. On the other hand, the 20 alpha-hydroxysteroid dehydrogenase gene was strongly expressed in the endometrium at the time of luteolysis. The corresponding recombinant enzyme has a K(m) of 7 microM for PGH(2) and a PGFS activity higher than the lung PGFS. This enzyme has two different activities with the ability to terminate the estrous cycle; it metabolizes progesterone and synthesizes PGF(2 alpha). Taken together, these data point to this newly identified enzyme as the functional endometrial PGFS.
authors.affiliation: Unité de Recherche en Ontogénie et Reproduction et Département d'Obstétrique et Gynécologie, Centre Hospitalier Universitaire de Québec, Université Laval, Sainte-Foy, Québec G1V 4G2, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Madore
authors.forename: Nathalie
authors.initials: N
authors.lastname: Harvey
authors.forename: Julie
authors.initials: J
authors.lastname: Parent
authors.forename: Pierre
authors.initials: P
authors.lastname: Chapdelaine
authors.forename: Joe A
authors.initials: JA
authors.lastname: Arosh
authors.forename: Michel A
authors.initials: MA
authors.lastname: Fortier
mesh_terms: D000449:Aldehyde Reductase / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D003349:Cortisone Reductase / Q000378:metabolism*; D017931:DNA Primers; D015232:Dinoprostone / Q000096:biosynthesis*; D004717:Endometrium / Q000201:enzymology / Q000378:metabolism*; D005260:Female; D007150:Immunohistochemistry; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D011994:Recombinant Proteins; D000449:Aldehyde Reductase; D003349:Cortisone Reductase; D015232:Dinoprostone