CHLORIDE CONDUCTANCE IN NASAL FIBROBLASTS OF PATIENTS WITH AND WITHOUT CYSTIC-FIBROSIS - RELEVANCE FOR THE OTOLARYNGOLOGIST

Cystic fibrosis (CF) is a complex systemic disease that has pathologic al alterations in the upper airways, including the recurrent formation of nasal polyps. Although the fibroblast is the predominant cell type in nasal stroma and nasal polyps, little is known about the electroph ysiological properties of nasal fibroblasts. We investigated whether f ibroblasts possess a cAMP-regulated chloride conductance which is impa ired in patients with CF. Thus far the few studies concerning conducta nce in fibroblasts have been performed on skin fibroblasts using indir ect methods and have yielded conflicting results. Therefore we studied chloride conductance in fused nasal fibroblasts by employing conventi onal microelectrodes. We have demonstrated that a cAMP-regulated chlor ide conductance is present in fibroblasts. However, this chloride cond uctance cannot be activated in fibroblasts from CF-patients. Thus, we present direct evidence that the impairment of the cAMP-regulated chlo ride conductance in CF is not confined to epithelial cells but also af fects the fibroblast. We discuss how this conductance might modulate f ibroblast proliferation to produce polyp formation.