title: Loss of endothelium-dependent relaxation in myometrial resistance arteries in pre-eclampsia.
abstract: OBJECTIVE
  To measure endothelium-dependent relaxation in myometrial resistance arteries and to compare this parameter in nonpregnant and normotensive pregnant women and those with pregnancies complicated by pre-eclampsia.
  
  
  METHODS
  A prospective study.
  
  
  METHODS
  Nottingham City Hospital.
  
  
  METHODS
  Thirty-seven nonpregnant women undergoing hysterectomy and 51 pregnant women undergoing caesarean section, of whom there were 39 normotensive and 12 with pre-eclampsia.
  
  
  METHODS
  Resistance arteries, dissected from myometrial biopsies, were mounted on a wire myograph and preconstricted with vasopressin then subjected to incremental doses of bradykinin.
  
  
  RESULTS
  Endothelium-dependent relaxation to bradykinin was seen in the vessels of nonpregnant and normotensive pregnant women. Markedly reduced endothelium-dependent relaxation was found in the myometrial arteries from women with pre-eclampsia when compared with both nonpregnant (P < 0.0001) and normotensive pregnant (P < 0.0001) women.
  
  
  CONCLUSIONS
  A significant loss of endothelium-dependent relaxation in myometrial resistance arteries in pre-eclampsia may contribute to the altered vasoreactivity seen in pre-eclampsia, and particularly to the decreased placental perfusion and fetal growth retardation commonly associated with this condition.
authors.affiliation: Department of Obstetrics and Gynaecology, Nottingham City Hospital, UK.
authors.forename: J R
authors.initials: JR
authors.lastname: Ashworth
authors.forename: A Y
authors.initials: AY
authors.lastname: Warren
authors.forename: P N
authors.initials: PN
authors.lastname: Baker
authors.forename: I R
authors.initials: IR
authors.lastname: Johnson
mesh_terms: D000328:Adult; D001158:Arteries / Q000187:drug effects / Q000503:physiopathology; D001920:Bradykinin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000502:physiology*; D005260:Female; D006801:Humans; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D009213:Myography; D009215:Myometrium / Q000098:blood supply*; D009638:Norepinephrine / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D011225:Pre-Eclampsia / Q000503:physiopathology*; D011247:Pregnancy; D011446:Prospective Studies; D014655:Vascular Resistance / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014667:Vasopressins / Q000494:pharmacology
chemical_list: D014662:Vasoconstrictor Agents; D014667:Vasopressins; D011188:Potassium; D001920:Bradykinin; D009638:Norepinephrine