title: Prenatal administration of retinoic acid upregulates insulin-like growth factor receptors in the nitrofen-induced hypoplastic lung.
abstract: BACKGROUND
  Pulmonary hypoplasia (PH) is the main cause of mortality in newborns with congenital diaphragmatic hernia (CDH). Prenatal administration of retinoic acid (RA) stimulates alveologenesis in the nitrofen-induced pulmonary hypoplasia. Insulin-like growth factor receptors (IGFRs) play a crucial role in alveologenesis during lung development. We recently demonstrated that IGFRs were downregulated in later stages of lung development in the nitrofen CDH model. Several studies suggest the ability of RA to regulate insulin-like growth factor signaling. We hypothesized that IGFRs pulmonary gene expression is upregulated after the administration of RA in the nitrofen-induced CDH model.
  
  
  METHODS
  Pregnant rats were exposed to either olive oil or nitrofen on day 9 (D9) of gestation. RA was given intraperitoneally on days D18, D19, and D20. Fetal lungs were dissected on D21 and divided into control, control + RA, CDH, and CDH + RA group. IGFRs gene and protein expression were determined using RT-PCR and immunohistochemistry.
  
  
  RESULTS
  mRNA expression levels of IGFRs were significantly increased in control + RA and CDH + RA compared with CDH group. Immunoreactivity of IGFRs was markedly increased in control + RA and CDH + RA compared with CDH lungs.
  
  
  CONCLUSIONS
  Upregulation of pulmonary gene and protein expression of IGFRs after prenatal RA treatment in the nitrofen model suggests that RA may promote lung growth by stimulating IGFRs mediated alveologenesis.
authors: National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland.
authors: Elke
authors: E
authors: Ruttenstock
authors: Takashi
authors: T
authors: Doi
authors: Jens
authors: J
authors: Dingemann
authors: Prem
authors: P
authors: Puri
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000187:drug effects; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006548:Hernia, Diaphragmatic / Q000473:pathology; D065630:Hernias, Diaphragmatic, Congenital; D007150:Immunohistochemistry; D008168:Lung / Q000002:abnormalities / Q000196:embryology*; D008171:Lung Diseases / Q000139:chemically induced* / Q000473:pathology; D010647:Phenyl Ethers / Q000633:toxicity*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000378:metabolism; D012333:RNA, Messenger; D051381:Rats; D017207:Rats, Sprague-Dawley; D017526:Receptor, IGF Type 1 / Q000378:metabolism*; D017527:Receptor, IGF Type 2 / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014212:Tretinoin / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D010647:Phenyl Ethers; D012333:RNA, Messenger; D017527:Receptor, IGF Type 2; D014212:Tretinoin; D017526:Receptor, IGF Type 1; C007350:nitrofen