Jan 1, 1992

Reversed anion selectivity in cultured cystic fibrosis sweat duct cells

The American Journal of Physiology
C L BellP M Quinton


The human genetic disease cystic fibrosis (CF) is characterized by defective epithelial Cl- conductance (GCl). To distinguish the CF-affected GCl from other Cl- channels, we have studied the properties of GCl in normal and CF cells grown from explanted reabsorptive sweat ducts (RD). The cultured cells from normal subjects retained some of the typical duct cell properties. The Na+ conductance inhibitor amiloride hyperpolarized intracellular potentials (Vm) by 10.4 +/- 1.6 mV (n = 12). Substitution of gluconate for Cl- depolarized Vm by 15.5 +/- 1.1 mV (n = 33). The apparent GCl (G'Cl) of normal cells was sensitive to adenosine 3',5'-cyclic monophosphate (forskolin, 10(-6) M), as evidenced by a significant increase (63%, n = 9) in the Cl- gradient induced depolarization, and more selective for Cl- than I- (substitution of Cl- by I- depolarized Vm by 6.3 +/- 0.3 mV, n = 49). Although the cells from CF subjects were statistically indistinguishable from normal cells based on Vm (-18.5 +/- 1.2 mV, n = 49 vs. -20.1 +/- 1.8 mV, n = 28), CF cells expressed differences in G'Cl, responses to forskolin, and anion selectivity. CF cells had a significantly reduced G'Cl as indicated by blunted responses to imposed Cl- gradients (26% of normal...Continue Reading

  • References
  • Citations25


  • We're still populating references for this paper, please check back later.

Mentioned in this Paper

Chorismate Lyase Activity
Chloride Ion Level
Entire Duct
Specimen Type - Sweat
Resting Potentials
Cystic Fibrosis

About this Paper

Related Feeds

Cardiac Conduction System

The cardiac conduction system is a specialized tract of myocardial cells responsible for maintaining normal cardiac rhythm. Discover the latest research on the cardiac conduction system here.