title: The effects of intrauterine growth restriction and antenatal glucocorticoids on ovine fetal lung development.
abstract: BACKGROUND
  Intrauterine growth restriction (IUGR) is associated with high rates of neonatal morbidity. IUGR babies are often born preterm and are, therefore, exposed to antenatal glucocorticoids. Antenatal glucocorticoids significantly improve overall survival rates of preterm infants, but there is a paucity of information about their effects on IUGR Infants.
  
  
  METHODS
  We induced IUGR in sheep by single umbilical artery ligation (SUAL), or sham in control fetuses. To half the ewes, we administered betamethasone (BM) on d 5 (BM1) and 6 (BM2) following surgery, and collected fetal lung tissue on d 7.
  
  
  RESULTS
  SUAL alone was associated with higher circulating fetal cortisol levels (2.8 ± 0.4 vs. 1.0 ± 0.4, P = 0.001) as compared with controls but not with changes in lung morphology or surfactant protein (SP) gene expression. BM was associated with a significant reduction in lung tissue density (P = 0.048). There were no significant differences between groups in lung DNA concentration or septal crest density. SP-A, SP-B, and SP-C gene expressions were significantly increased in control and SUAL fetuses that were administered BM.
  
  
  CONCLUSIONS
  These results show that in SUAL fetuses, maternal BM is associated with acceleration of fetal lung structure, as occurs in normally grown fetuses, and that BM induces SP production, an effect not observed in SUAL-induced IUGR fetuses alone.
authors.affiliation: The Ritchie Centre, Monash Institute of Medical Research, Monash University, Clayton, Victoria, Australia.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Sutherland
authors.forename: Kelly J
authors.initials: KJ
authors.lastname: Crossley
authors.forename: Beth J
authors.initials: BJ
authors.lastname: Allison
authors.forename: Graham
authors.initials: G
authors.lastname: Jenkin
authors.forename: Euan M
authors.initials: EM
authors.lastname: Wallace
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Miller
mesh_terms: D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D001623:Betamethasone / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D047109:Fetal Development / Q000187:drug effects*; D005317:Fetal Growth Retardation / Q000209:etiology / Q000503:physiopathology*; D006854:Hydrocortisone / Q000097:blood; D007273:Injections, Intramuscular; D008026:Ligation; D008168:Lung / Q000187:drug effects / Q000196:embryology* / Q000378:metabolism; D023421:Models, Animal; D011247:Pregnancy; D037662:Pulmonary Surfactant-Associated Protein A / Q000378:metabolism; D037701:Pulmonary Surfactant-Associated Protein B / Q000378:metabolism; D037721:Pulmonary Surfactant-Associated Protein C / Q000378:metabolism; D012756:Sheep; D014469:Umbilical Arteries / Q000503:physiopathology
chemical_list: D000305:Adrenal Cortex Hormones; D037662:Pulmonary Surfactant-Associated Protein A; D037701:Pulmonary Surfactant-Associated Protein B; D037721:Pulmonary Surfactant-Associated Protein C; D001623:Betamethasone; D006854:Hydrocortisone