title: Rapid modulation of ovarian 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase gene expression by prolactin and human chorionic gonadotropin in the hypophysectomized rat.
abstract: In order to better understand the role of prolactin (PRL) and luteinizing hormone (LH) on progesterone biosynthesis in the ovary, we have investigated the time course (1-9 days) of the effect of PRL and human chorionic gonadotropin (hCG) on ovarian 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD) expression in the hypophysectomized rat. As evaluated by quantitative in situ hybridization using a 35S labelled type I 3 beta-HSD cDNA probe, the administration of hCG for 2, 3 and 9 days induced increases of 63%, 145% and 146% above control, respectively, in 3 beta-HSD mRNA levels in ovarian interstitial cells. The absence of apparent effect of the gonadotropin in other ovarian cell types could explain the small modulation of ovarian 3 beta-HSD protein content and enzymatic activity observed in total ovarian tissue. On the other hand, treatment with PRL caused a rapid decrease in 3 beta-HSD mRNA levels in corpus luteum by 23%, 63%, 76% and 78% (P < 0.01) following 1, 2, 5 and 9 days of treatment, respectively. The short-term inhibitory effect of PRL was also observed on ovarian immunoreactive 3 beta-HSD protein, as measured by Western blot analysis, and on 3 beta-HSD activity measured by the conversion of [14C]dehydroepiandrosterone into [14C]androstenedione.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Medical Research Council Group in Molecular Endocrinology, CHUL Research Center, Ste. Foy, Quebec, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Martel
authors.forename: D
authors.initials: D
authors.lastname: Gagné
authors.forename: J
authors.initials: J
authors.lastname: Couet
authors.forename: Y
authors.initials: Y
authors.lastname: Labrie
authors.forename: J
authors.initials: J
authors.lastname: Simard
authors.forename: F
authors.initials: F
authors.lastname: Labrie
mesh_terms: D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D003338:Corpus Luteum / Q000187:drug effects / Q000201:enzymology; D018076:DNA, Complementary / Q000235:genetics; D004790:Enzyme Induction / Q000187:drug effects; D005260:Female; D007016:Hypophysectomy; D017403:In Situ Hybridization; D009097:Multienzyme Complexes / Q000096:biosynthesis* / Q000235:genetics; D009929:Organ Size / Q000187:drug effects; D010053:Ovary / Q000033:anatomy & histology / Q000187:drug effects* / Q000201:enzymology; D011284:Pregnenolone / Q000097:blood; D011374:Progesterone / Q000097:blood; D011375:Progesterone Reductase / Q000096:biosynthesis* / Q000235:genetics; D011388:Prolactin / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013251:Steroid Isomerases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: C021425:3 beta-hydroxysteroid oxidoreductase-delta(5) 3-ketosteroid isomerase; D006063:Chorionic Gonadotropin; D018076:DNA, Complementary; D009097:Multienzyme Complexes; D011374:Progesterone; D011284:Pregnenolone; D011388:Prolactin; D011375:Progesterone Reductase; D013251:Steroid Isomerases