title: Intrauterine growth restriction transiently delays alveolar formation and disrupts retinoic acid receptor expression in the lung of female rat pups.
abstract: BACKGROUND
  We showed that intrauterine growth restriction (IUGR) increases distal airspace wall thickness at birth (postnatal age 0; P0) in rat pups (saccular stage of lung development). However, that report did not assess whether the saccular phenotype persisted postnatally or occurred in males or females, nor did the report identify a potential molecular pathway for the saccular phenotype at P0. We hypothesized that IUGR persistently delays alveolar formation and disrupts retinoic acid receptor (RAR) mRNA and protein levels in the lung of rat pups in a postnatal age- and sex-specific manner.
  
  
  METHODS
  IUGR was induced in pregnant rats by bilateral uterine artery ligation. Alveolar formation and expression of RARα, -β, and -γ were quantified at P0, P6 (alveolar stage), and P21 (postalveolarization).
  
  
  RESULTS
  IUGR increased distal airspace wall thickness in female pups at P0 only. IUGR did not affect male pups at any age. IUGR transiently increased lung RAR-β protein abundance, which inhibits alveolar formation, at P0 in female pups. Serum retinol concentration was normal at all ages.
  
  
  CONCLUSIONS
  IUGR alone is not sufficient to persistently delay postnatal alveolar formation or disrupt expression of RARs. We speculate that for IUGR to delay alveolar formation postnatally, a second insult is necessary.
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Lisa
authors: L
authors: Joss-Moore
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Travis
authors: T
authors: Carroll
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Yan
authors: Y
authors: Yang
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Melanie
authors: M
authors: Fitzhugh
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Drew
authors: D
authors: Metcalfe
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Jake
authors: J
authors: Oman
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Merica
authors: M
authors: Hale
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Li
authors: L
authors: Dong
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Zheng-Ming
authors: ZM
authors: Wang
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Xing
authors: X
authors: Yu
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Christopher W
authors: CW
authors: Callaway
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Elizabeth
authors: E
authors: O'Brien
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Robert A
authors: RA
authors: McKnight
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Robert H
authors: RH
authors: Lane
authors: Department of Pediatrics, University of Utah, Salt Lake City, UT.
authors: Kurt H
authors: KH
authors: Albertine
mesh_terms: D000818:Animals; D005260:Female; D005317:Fetal Growth Retardation; D008168:Lung / Q000196:embryology / Q000378:metabolism*; D011247:Pregnancy; D011650:Pulmonary Alveoli / Q000196:embryology*; D051381:Rats; D018168:Receptors, Retinoic Acid / Q000378:metabolism*
chemical_list: D018168:Receptors, Retinoic Acid