title: The effects of a cyclo-oxygenase II inhibitor on placental artery production of thromboxane and prostacyclin.
abstract: OBJECTIVE
  The study was undertaken to determine the effects of a cyclo-oxygenase II inhibitor on fetoplacental artery production of prostacyclin and thromboxane A(2).
  
  
  METHODS
  Eight placentas were obtained from normal parturients at delivery and four chorionic plate arteries were dissected from each placenta. Arteries were incubated in media alone, media plus angiotensin II (1x10(-10) mol), media plus rofecoxib (300 ng/mL), or media plus angiotensin II and rofecoxib. Serial samples were assayed for metabolites of thromboxane B(2) and prostacyclin by enzyme-linked immunosorbent assay. Results were compared by analysis of variance, and P<.05 was considered significant.
  
  
  RESULTS
  At 24 hours, 6-keto-prostaglandin F(1alpha) levels in the rofecoxib group (1.74+/-1.39 ng/mg tissue, P<.01) and the rofecoxib plus angiotensin II group (2.15+/-1.85 ng/mg tissue, P<.01) were significantly lower than levels in the control group (4.25+/-2.03 ng/mg tissue). Thromboxane B(2) levels were lower in the angiotensin II group (0.65+/-0.33 ng/mg tissue) than the control group (1.22+/-0.70 ng/mg tissue, P<.05).
  
  
  CONCLUSIONS
  Cyclo-oxygenase II inhibition decreases the production of prostacyclin in fetoplacental arteries and alters the normal ratio of thromboxane A(2) to prostacyclin.
authors.affiliation: Madigan Army Medical Center, Tacoma, WA 98431, USA. Bobby.Howard@nw.amedd.army.mil
authors.forename: Bobby C
authors.initials: BC
authors.lastname: Howard
authors.forename: Christine M
authors.initials: CM
authors.lastname: Kovac
authors.forename: Byron C
authors.initials: BC
authors.lastname: Calhoun
authors.forename: Nathan J
authors.initials: NJ
authors.lastname: Hoeldtke
authors.forename: Peter G
authors.initials: PG
authors.lastname: Napolitano
mesh_terms: D000804:Angiotensin II / Q000494:pharmacology; D001158:Arteries / Q000187:drug effects* / Q000378:metabolism; D003470:Culture Media; D046508:Culture Techniques; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D015237:Dinoprost / Q000096:biosynthesis; D011464:Epoprostenol / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors*; D007783:Lactones / Q000494:pharmacology; D008565:Membrane Proteins; D010920:Placenta / Q000098:blood supply*; D011247:Pregnancy; D011451:Prostaglandin-Endoperoxide Synthases; D013450:Sulfones; D013928:Thromboxane A2 / Q000096:biosynthesis*
chemical_list: C078129:6-keto-prostaglandin F2alpha; D003470:Culture Media; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D007527:Isoenzymes; D007783:Lactones; D008565:Membrane Proteins; D013450:Sulfones; C116926:rofecoxib; D000804:Angiotensin II; D013928:Thromboxane A2; D015237:Dinoprost; D011464:Epoprostenol; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases