Activation of endogenous deltaF508 cystic fibrosis transmembrane conductance regulator by phosphodiesterase inhibition

J Clin Invest. 1996 Jul 15;98(2):513-20. doi: 10.1172/JCI118819.

Abstract

Many heterologously expressed mutants of the cystic fibrosis transmembrane conductance regulator (CFTR) exhibit residual chloride channel activity that can be stimulated by agonists of the adenylate cyclase/protein kinase A pathway. Because of clinical implications for cystic fibrosis of activating mutants in vivo, we are investigating whether deltaF508, the most common disease-associated CFTR mutation, can be activated in airway epithelial cells. We have found that, 36Cl- efflux can be stimulated 19-61% above baseline by beta-adrenoreceptor agonists and cGI-phosphodiesterase inhibitors in transformed nasal polyp (CF-T43) cells homozygous for the deltaF508 mutation. The increase in 36Cl- permeability is diminished by protein kinase A inhibitors and is not mediated by an increase in intracellular calcium concentrations. Preincubation of CF-T43 cells with CFTR anti-sense oligonucleotides prevented an increase in 36Cl- efflux in response to beta-agonist and phosphodiesterase inhibitor. Primary cells isolated from CF nasal polyps gave similar results. These data indicate that endogenous levels of deltaF508 protein can be stimulated to increase 36Cl- permeability in airway epithelial cells.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 1-Methyl-3-isobutylxanthine / pharmacology
  • Adrenergic beta-Agonists / pharmacology
  • Albuterol / pharmacology
  • Base Sequence
  • Calcium / metabolism
  • Cell Line
  • Chlorides / metabolism*
  • Cyclic AMP / analogs & derivatives
  • Cyclic AMP / metabolism
  • Cyclic AMP / pharmacology
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors
  • Cystic Fibrosis / physiopathology
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics
  • Cystic Fibrosis Transmembrane Conductance Regulator / metabolism*
  • Drug Synergism
  • Egtazic Acid / analogs & derivatives
  • Egtazic Acid / pharmacology
  • Enzyme Inhibitors / pharmacology
  • Epithelium
  • Humans
  • Isoproterenol / pharmacology
  • Kinetics
  • Membrane Potentials / drug effects
  • Milrinone
  • Molecular Sequence Data
  • Oligodeoxyribonucleotides
  • Oligonucleotides, Antisense
  • Phosphodiesterase Inhibitors / pharmacology*
  • Pyridones / pharmacology*
  • Thionucleotides / pharmacology

Substances

  • Adrenergic beta-Agonists
  • CFTR protein, human
  • Chlorides
  • Enzyme Inhibitors
  • Oligodeoxyribonucleotides
  • Oligonucleotides, Antisense
  • Phosphodiesterase Inhibitors
  • Pyridones
  • Thionucleotides
  • Cystic Fibrosis Transmembrane Conductance Regulator
  • adenosine-3',5'-cyclic phosphorothioate
  • Egtazic Acid
  • Cyclic AMP
  • Cyclic AMP-Dependent Protein Kinases
  • Milrinone
  • 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid
  • Isoproterenol
  • Albuterol
  • Calcium
  • 1-Methyl-3-isobutylxanthine