Skip to main page content
U.S. flag

An official website of the United States government

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 1997 Nov 15;100(10):2588-95.
doi: 10.1172/JCI119802.

Ion composition of airway surface liquid of patients with cystic fibrosis as compared with normal and disease-control subjects

M R Knowles  1 , J M Robinson, R E Wood, C A Pue, W M Mentz, G C Wager, J T Gatzy, R C Boucher
Affiliations
Comparative Study

Ion composition of airway surface liquid of patients with cystic fibrosis as compared with normal and disease-control subjects

M R Knowles et al. J Clin Invest. .

Erratum in

  • J Clin Invest 1998 Jan 1;101(1):285

Abstract

To test whether a major contribution of airways epithelial ion transport to lung defense reflects the regulation of airway surface liquid (ASL) ionic composition, we measured ASL composition using the filter paper technique. On nasal surfaces, the Cl- concentration (approximately 125 meq/liter) was similar to plasma, but the Na+ concentration (approximately 110 meq/liter) was below plasma, and K+ concentration (approximately 30 meq/liter) above plasma. The resting ASL osmolarity [2(Na+ + K+); 277 meq/liter] approximated isotonicity. There were no detectable differences between cystic fibrosis (CF) and normal subjects. In the lower airways, the Na+ concentrations were 80-85 meq/liter, K+ levels approximately 15 meq/liter, and Cl- concentrations 75-80 meq/liter. Measurements of Na+ activity with Na(+)-selective electrodes and osmolality with freezing point depression yielded values consistent with the monovalent cation measurements. Like the nasal surfaces, no differences in cations were detected between CF, normal, or chronic bronchitis subjects. The tracheobronchial ASL hypotonicity was hypothesized to reflect collection-induced gland secretion, a speculation consistent with observations in which induction of nasal gland secretion produced hypotonic secretions. We conclude that there are no significant differences in ASL ion concentrations between CF, normal, and chronic bronchitis subjects and, because ASL ion concentrations exceed values consistent with defensin activity, the failure of CF lung defense may reflect predominantly factors other than salt-dependent defensins.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. J Appl Physiol (1985). 1994 Nov;77(5):2333-40 - PubMed
    1. Am J Respir Crit Care Med. 1994 Aug;150(2):581-93 - PubMed
    1. J Appl Physiol (1985). 1995 Jun;78(6):2020-4 - PubMed
    1. Am J Respir Cell Mol Biol. 1996 Jan;14(1):104-12 - PubMed
    1. Cell. 1996 Apr 5;85(1):1-4 - PubMed

Publication types