Electrical Properties of Tracheal Epithelium in Cystic Fibrosis

To the Editor: As reported by Knowles et al. in the issue of December 17, 1981, in vivo measurements of potential difference across the trachea in patients with cystic fibrosis were significantly greater than in control subjects. (P<0.05).* Superfusion of the luminal surface of the trachea with amiloride (10-4 M) reduced the potential difference by 85 per cent in patients, as compared with 25 per cent in controls, suggesting that the increased potential difference in cystic fibrosis is due to an increase in amiloride-sensitive sodium absorption