title: Quantitative detection of EP3-II, III and VI messenger RNA in gravid and non-gravid human myometrium using real-time RT-PCR.
abstract: OBJECTIVE
  To examine mRNA expression of prostaglandin E2 receptor isoforms EP3-II, III and VI in lower uterine segment myometrium in the non-pregnant and pregnant state using quantitative real-time RT-PCR.
  
  
  METHODS
  Myometrial samples were obtained at the time of cesarean delivery or hysterectomy. Pregnant subjects were categorised based on the presence or absence of labour. Labour was defined as regular uterine contractions resulting in cervical change. Quantification for EP3 isoforms II, III and VI mRNA was performed using real-time RT-PCR.
  
  
  RESULTS
  There were no differences between non-pregnant and non-labouring pregnant subjects in mRNA expression of EP3-II, III and VI. However, when compared to pregnant subjects not in labour, labouring subjects had a 3.8-fold reduction in EP3-II expression (p < 0.001) and 5.3-fold reduction in EP3-VI expression (p = 0.022).
  
  
  CONCLUSIONS
  In human parturition, there is decreased mRNA expression of lower-uterine segment EP3 receptor isoforms II and VI during labour. This may reflect differential relaxation of the lower segment of the uterus allowing dilatation and descent of the fetus.
authors.affiliation: Department of Obstetrics and Gynecology, Los Angeles County-University of Southern California Medical Center, Women's and Children's Hospital, Los Angeles County, California, USA. richarhl@usc.edu
authors.forename: Richard H
authors.initials: RH
authors.lastname: Lee
authors.forename: T Murphy
authors.initials: TM
authors.lastname: Goodwin
authors.forename: Wangrong
authors.initials: W
authors.lastname: Yang
authors.forename: Aimin
authors.initials: A
authors.lastname: Li
authors.forename: Melissa L
authors.initials: ML
authors.lastname: Wilson
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Mullin
authors.forename: Juan C
authors.initials: JC
authors.lastname: Felix
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000235:genetics / Q000378:metabolism; D009215:Myometrium / Q000378:metabolism*; D010298:Parity / Q000235:genetics; D011247:Pregnancy; D011263:Pregnancy Trimester, Third / Q000235:genetics* / Q000378:metabolism; D020033:Protein Isoforms / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D018078:Receptors, Prostaglandin E / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D058308:Receptors, Prostaglandin E, EP3 Subtype; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
chemical_list: C545647:PTGER3 protein, human; D020033:Protein Isoforms; D012333:RNA, Messenger; D018078:Receptors, Prostaglandin E; D058308:Receptors, Prostaglandin E, EP3 Subtype