title: Neuronal nitric oxide synthase does not contribute to the modulation of pulmonary vascular tone in fetal lambs with congenital diaphragmatic hernia (nNOS in CDH lambs).
abstract: OBJECTIVE
  The aim of this study was to determine the presence of the neuronal nitric oxide synthase (nNOS) in near full-term lambs with congenital diaphragmatic hernia (CDH) and its role in the modulation of pulmonary vascular basal tone.
  
  
  METHODS
  We surgically created diaphragmatic hernia on the 85th day of gestation. On the 135th, catheters were used to measure pulmonary pressure and blood flow. We tested the effects of 7-nitroindazole (7-NINA), a specific nNOS antagonist and of N-nitro-L-arginine (L-NNA), a nonspecific nitric oxide synthase antagonist. In vitro, we tested the effects of the same drugs on isolated pulmonary vessels. The presence of nNOS protein in the lungs was detected by Western blot analysis.
  
  
  RESULTS
  Neither 7-NINA nor L-NNA modified pulmonary vascular basal tone in vivo. After L-NNA injection, acetylcholine (ACh) did not decrease significantly pulmonary vascular resistance (PVR). In vitro, L-NNA increased the cholinergic contractile-response elicited by electric field stimulation (EFS) of vascular rings from lambs with diaphragmatic hernia.
  
  
  CONCLUSIONS
  We conclude that nNOS protein is present in the lungs and pulmonary artery of near full-term lamb fetuses with diaphragmatic hernia, but that it does not contribute to the reduction of pulmonary vascular tone at birth.
authors.affiliation: Faculté de Médecine, Université Paris Descartes, EA 2511, Assistance Publique Hôpitaux de Paris, Service de Physiologie-Explorations Fonctionnelles, Hôpital Cochin, Paris, France. anthony.debuys-roessingh@chuv.ch
authors.forename: Anthony S
authors.initials: AS
authors.lastname: de Buys Roessingh
authors.forename: Pascal
authors.initials: P
authors.lastname: de Lagausie
authors.forename: Taline
authors.initials: T
authors.lastname: Ebrahimian
authors.forename: Taline
authors.initials: T
authors.lastname: Ibrahima
authors.forename: Sy
authors.initials: S
authors.lastname: Duong-Quy
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Schneider
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Huang
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Mercier
authors.forename: Yves
authors.initials: Y
authors.lastname: Aigrain
authors.forename: Chantal
authors.initials: C
authors.lastname: Boulanger
authors.forename: Anh Tuan
authors.initials: AT
authors.lastname: Dinh-Xuan
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D015153:Blotting, Western; D004195:Disease Models, Animal; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005333:Fetus / Q000187:drug effects / Q000201:enzymology; D005865:Gestational Age; D006339:Heart Rate / Q000187:drug effects; D006548:Hernia, Diaphragmatic / Q000201:enzymology / Q000503:physiopathology*; D065630:Hernias, Diaphragmatic, Congenital; D008168:Lung / Q000098:blood supply / Q000187:drug effects / Q000503:physiopathology*; D052248:Nitric Oxide Synthase Type I / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009924:Organ Culture Techniques; D011651:Pulmonary Artery / Q000187:drug effects / Q000201:enzymology / Q000503:physiopathology*; D011652:Pulmonary Circulation / Q000187:drug effects; D012756:Sheep; D014655:Vascular Resistance / Q000187:drug effects
chemical_list: D004791:Enzyme Inhibitors; D052248:Nitric Oxide Synthase Type I