title: The regulation of the prolactin receptor gene expression in the mammary gland of early pregnant mouse.
abstract: The purpose of this research was to examine the hormonal regulation of the PRL receptor (PRL-R) gene expression in the mammary gland of early pregnant mouse. Following reverse-transcription, the quantity of PRL-R mRNA was determined by the competitive polymerase chain reaction. The level of long form PRL-R (PRL-RL) mRNA changed cyclically with the highest at estrus and the lowest at diestrus II. PRL-RL mRNA was maintained at high levels for the first 3 days of pregnancy but declined to lower levels on day 5. Mice ovariectomized on day 2 of pregnancy maintained the same level of PRL-RL mRNA during the 24 h-period. The level of PRL-R mRNA increased more than 2- and 2.7-fold with 17 beta-estradiol and PRL, respectively, and the progesterone concentration decreased its levels to 71% of the vehicle-injected control. The increasing action with 17 beta-estradiol and PRL was suppressed by administration of progesterone. Mice ovariectomized on day 3 had a 1.8-fold higher level than that of the sham-operated control. The short form of PRL-R remained at low levels throughout the experiments. The results suggested that the expression of the PRL-R gene was suppressed when serum progesterone increased during early pregnancy.
authors.affiliation: Department of Animal Breeding, Faculty of Agriculture, University of Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Mizoguchi
authors.forename: J Y
authors.initials: JY
authors.lastname: Kim
authors.forename: J
authors.initials: J
authors.lastname: Enami
authors.forename: S
authors.initials: S
authors.lastname: Sakai
mesh_terms: D000818:Animals; D018076:DNA, Complementary / Q000032:analysis / Q000235:genetics; D004958:Estradiol / Q000494:pharmacology; D004971:Estrus / Q000187:drug effects / Q000235:genetics*; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000235:genetics*; D008321:Mammary Glands, Animal / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008813:Mice, Inbred ICR; D010052:Ovariectomy; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D011374:Progesterone / Q000494:pharmacology; D011388:Prolactin / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis / Q000187:drug effects / Q000235:genetics; D011981:Receptors, Prolactin / Q000187:drug effects / Q000235:genetics*
chemical_list: D018076:DNA, Complementary; D012333:RNA, Messenger; D011981:Receptors, Prolactin; D011374:Progesterone; D004958:Estradiol; D011388:Prolactin