title: Onapristone suppresses prolactin production in explant cultures of leiomyoma.
abstract: OBJECTIVE
  To assess the action of onapristone, a type I antiprogestin, on prolactin (PRL) production by explant cultures of leiomyoma and myometrium.
  
  
  METHODS
  Explant cultures of myometrium and leiomyomas from 3 premenopausal women undergoing hysterectomy in the proliferative phase of the menstrual cycle.
  
  
  METHODS
  PRL secretion measured by radioimmunoassay.
  
  
  RESULTS
  PRL secretion was decreased in leiomyomas by onapristone. There was no effect in the myometrium. There was no additional effect with the addition of the type II antiprogestin mifepristone (RU 486).
  
  
  CONCLUSIONS
  PRL production is suppressed in leiomyomas but not in myometrium after treatment with onapristone in vitro. This suppression may serve as a marker for the clinical effectiveness of agents used in the treatment of leiomyomas.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Brigham and Women's Hospital, Boston, Mass., USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Austin
authors.forename: R A
authors.initials: RA
authors.lastname: Nowak
authors.forename: E A
authors.initials: EA
authors.lastname: Stewart
mesh_terms: D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D005260:Female; D006067:Gonanes / Q000008:administration & dosage / Q000494:pharmacology*; D006727:Hormone Antagonists / Q000494:pharmacology*; D006801:Humans; D007044:Hysterectomy; D007889:Leiomyoma / Q000378:metabolism*; D009215:Myometrium / Q000187:drug effects / Q000378:metabolism; D017697:Premenopause; D011372:Progestins / Q000037:antagonists & inhibitors; D011388:Prolactin / Q000096:biosynthesis* / Q000378:metabolism; D014594:Uterine Neoplasms / Q000378:metabolism*
chemical_list: D006067:Gonanes; D006727:Hormone Antagonists; D011372:Progestins; D011388:Prolactin; C053238:onapristone