Decreased sodium ion absorption across nasal epithelium of very premature infants with respiratory distress syndrome

J Pediatr. 1997 Mar;130(3):373-7. doi: 10.1016/s0022-3476(97)70198-7.


Objective and study design: Successful adaptation to air breathing at birth depends on rapid absorption of fetal lung liquid that is mediated by activation of amiloride-sensitive sodium ion channels. To test the relationship between respiratory epithelial Na+ transport and development of respiratory distress syndrome (RDS), we measured nasal transepithelial potential difference (PD) in 31 very premature (< or = 30 weeks of gestation) newborn infants. Infants were retrospectively assigned to RDS (22 infants) and non-RDS (9 infants) groups on the basis of clinical and chest x-ray criteria.

Results: Maximal nasal epithelial PD increased with birth weight (-1.2 mV/100 gm) and was lower in infants with RDS (-16.5 +/- 0.6 mV) than in those without RDS (-22.0 +/- 1.3 mV). Infants without RDS had PD values similar to normal fullterm infants. Amiloride inhibition of PD, an index of Na+ absorption, was significantly lower, within the first 24 hours of life, in infants in whom RDS developed (3.8 +/- 0.2 mV; 29.5% +/- 0.8% inhibition) than in those without RDS (6.1 +/- 0.6 mV; 38.6% +/- 0.5% inhibition). Maximal and amiloride-sensitive PD returned to normal during the recovery phase of RDS.

Conclusions: We conclude that Na+ absorption across nasal epithelium increases with increasing birth weight and that impairment of Na+ absorption across the respiratory epithelia of very premature infants may contribute to the pathogenesis of RDS.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amiloride / pharmacology
  • Biological Transport, Active
  • Birth Weight
  • Case-Control Studies
  • Humans
  • Infant, Newborn
  • Infant, Premature
  • Nasal Mucosa / metabolism*
  • Respiratory Distress Syndrome, Newborn / etiology
  • Respiratory Distress Syndrome, Newborn / metabolism*
  • Respiratory Distress Syndrome, Newborn / therapy
  • Sodium / metabolism*
  • Sodium Channel Blockers
  • Sodium Channels / metabolism


  • Sodium Channel Blockers
  • Sodium Channels
  • Amiloride
  • Sodium