title: A longer tracheal occlusion period results in increased lung growth in the nitrofen rat model.
abstract: OBJECTIVE
  Prenatal tracheal occlusion (TO) promotes lung growth and is applied clinically in fetuses with severe congenital diaphragmatic hernia. Limited data are available regarding the effect of duration of TO on lung development. Our objective was to evaluate the effects of long (2 and 2.5 days) versus short (1 day) TO on lung development in rats with nitrofen-induced diaphragmatic hernia.
  
  
  METHODS
  Nitrofen was administered on embryonic day (ED) 9 and fetal TO performed either on ED18.5, 19 or 20 (term = 22 days). Sham-operated and untouched littermates served as controls. On ED21, lungs were harvested and only fetuses with a left-sided diaphragmatic defect were included in further analyses.
  
  
  RESULTS
  Lung-body-weight ratio incrementally increased with the duration of TO. Increased proliferation following long TO was confirmed by immunohistochemistry and qRT-PCR for the proliferation marker Ki-67. Irrespective of duration, TO induced more complex airway architecture. Medial wall thickness of pulmonary arteries was thinner after long rather than short TO.
  
  
  CONCLUSIONS
  In the nitrofen rat model of congenital diaphragmatic hernia, a longer period of TO leads to enhanced lung growth and less muscularized pulmonary arteries.
authors: Department of Obstetrics and Gynaecology, Division Woman and Child, University Hospital Gasthuisberg, Herestraat 49, Leuven, Belgium.
authors: Veronika
authors: V
authors: Beck
authors: Marcus G
authors: MG
authors: Davey
authors: Steffi
authors: S
authors: Mayer
authors: Guy
authors: G
authors: Froyen
authors: Sebastiaan
authors: S
authors: Deckx
authors: Philipp
authors: P
authors: Klaritsch
authors: Xenia I
authors: XI
authors: Roubliova
authors: Scott G
authors: SG
authors: Petersen
authors: Jan A
authors: JA
authors: Deprest
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D004195:Disease Models, Animal; D005260:Female; D005315:Fetal Diseases / Q000601:surgery*; D005333:Fetus / Q000002:abnormalities / Q000601:surgery; D005865:Gestational Age; D006540:Herbicides / Q000633:toxicity; D006548:Hernia, Diaphragmatic / Q000139:chemically induced / Q000473:pathology / Q000601:surgery; D065630:Hernias, Diaphragmatic, Congenital; D008168:Lung / Q000187:drug effects / Q000196:embryology* / Q000473:pathology; D009929:Organ Size; D010647:Phenyl Ethers / Q000633:toxicity; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014132:Trachea / Q000601:surgery*
chemical_list: D006540:Herbicides; D010647:Phenyl Ethers; C007350:nitrofen