title: Oxytocin, its antagonist Atosiban, and preterm labor: a role for placental nitric oxide.
abstract: OBJECTIVE
  The aim of the present study was to understand the role played by Atosiban, an oxytocin receptor antagonist, on trophoblastic human cells, and the molecular bases of its efficacy and safety in the treatment of preterm labor. NO, peroxinitrite production and NOS expression have been evaluated on placenta obtained from term and preterm labors.
  
  
  METHODS
  We studied trophoblast cells isolated from selected placental tissue from 20 controls and 20 preterm patients after cesarean sections. Each sample was studied at basal state and after 2 hours incubation with oxytocin and Atosiban.
  
  
  RESULTS
  Significant variations of NO levels, peroxynitrite production and iNOS and eNOS expression both in the preterm, term samples and in each of the considered groups were observed. In the control group Atosiban re-established NO levels that were reduced after incubation with oxytocin, while in preterm samples NO levels were not only re-established but, after incubation with Atosiban, significantly increased compared to basal levels.
  
  
  CONCLUSIONS
  This confirms the beneficial role of Atosiban in prolonging the pregnancy of spontaneous labor at very early gestational periods. In conclusion, Atosiban might be an effective drug to prevent preterm labor, in the therapeutic approach to this pathology.
authors.affiliation: Section of Biochemistry, Biology and Physics and.
authors.forename: Laura
authors.initials: L
authors.lastname: Nanetti
authors.forename: Francesca
authors.initials: F
authors.lastname: Raffaelli
authors.forename: Alessia
authors.initials: A
authors.lastname: Giulietti
authors.forename: Giulia
authors.initials: G
authors.lastname: Sforza
authors.forename: Stefano
authors.initials: S
authors.lastname: Raffaele Giannubilo
authors.forename: Andrea
authors.initials: A
authors.lastname: Ciavattini
authors.forename: Andrea Luigi
authors.initials: AL
authors.lastname: Tranquilli
authors.forename: Laura
authors.initials: L
authors.lastname: Mazzanti
authors.forename: Arianna
authors.initials: A
authors.lastname: Vignini
mesh_terms: D016022:Case-Control Studies; D002478:Cells, Cultured; D005260:Female; D006727:Hormone Antagonists / Q000627:therapeutic use; D006801:Humans; D007231:Infant, Newborn; D009569:Nitric Oxide / Q000378:metabolism*; D007752:Obstetric Labor, Premature / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D010121:Oxytocin / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D010920:Placenta / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D015149:Tocolytic Agents / Q000627:therapeutic use*; D014668:Vasotocin / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D006727:Hormone Antagonists; D015149:Tocolytic Agents; C047046:atosiban; D009569:Nitric Oxide; D010121:Oxytocin; D014668:Vasotocin
keywords: Atosiban; eNOS; iNOS; nitric oxide; oxytocin; peroxynitrite; trophoblasts