title: Effects of nitric oxide and prostacyclin on hemodynamic response by big endothelin-1 in near term fetal sheep.
abstract: OBJECTIVE
  To measure plasma concentrations of endothelin (ET)-1, NO metabolites (nitrate/nitrite; NOx) and 6-keto PGF1 alpha (PGF1 alpha) in maternal and fetal sheep blood, and to evaluate the effects of big ET-1 on hemodynamic response, blood gases and NO and 6-keto PGF1 alpha production in near term fetal sheep.
  
  
  METHODS
  Hemodynamic parameters were measured during infusion of big ET-1 into the carotid vein in chronically catheterized fetal sheep on day 125 of gestation. Fetal arterial blood samples were obtained for ET-1, PGF1 alpha) and nitrate/nitrite (NOx) measurements.
  
  
  RESULTS
  ET-1, NOx and PGF1 alpha plasma concentrations were all significantly higher in fetal compared with the maternal plasma. Big ET-1 significantly decreased fetal systolic and diastolic blood pressure and significantly increased fetal heart rate. Big ET-1 stimulated plasma PGF1 alpha), but not NOx , concentration.
  
  
  CONCLUSIONS
  Circulatory regulating factors in the fetus were up-regulated. The effects of ET-1 on fetal hemodynamic response may be mediated via prostacyclin, but not via the NO pathway.
authors.affiliation: Department of Obstetrics and Gynecology, Fukushima Medical University School of Medicine, Fukushima 960-1295, Japan. okawat@fmu.ac.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Okawa
authors.forename: Shinya
authors.initials: S
authors.lastname: Honda
authors.forename: Minoru
authors.initials: M
authors.lastname: Sanpei
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Ishida
authors.forename: Keiya
authors.initials: K
authors.lastname: Fujimori
authors.forename: Akira
authors.initials: A
authors.lastname: Sato
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis; D019332:Endothelin-1 / Q000097:blood / Q000494:pharmacology*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006439:Hemodynamics / Q000187:drug effects; D009569:Nitric Oxide / Q000097:blood*; D011247:Pregnancy; D011460:Prostaglandins F / Q000097:blood*; D012756:Sheep
chemical_list: D019332:Endothelin-1; D011460:Prostaglandins F; D009569:Nitric Oxide; C100006:prostaglandin F1