Evidence for reduced Cl‐ and increased Na+ permeability in cystic fibrosis human primary cell cultures.

作者：Richard C. Boucher, Calvin U. Cotton, J. T. Gatzy, Michael R. Knowles, James R. Yankaskas · 发表于：The Journal of Physiology · 年份：1988 · DOI：10.1113/jphysiol.1988.sp017322 · 被引用次数：270 · 研究领域：Advanced Chemical Sensor Technologies、Planarian Biology and Electrostimulation、Plant and Biological Electrophysiology Studies

1. Employing a primary cell culture system and intracellular microelectrodes, we quantitated and compared the Na+ and Cl- pathways in apical membranes of normal and cystic fibrosis (CF) human airway epithelia. 2. Like the transepithelial difference (PD) in situ, the PD of CF epithelia in culture (-27 +/- 4 mV, mean +/- S.E.M.; n = 28) exceeded the PD of normal epithelia (-10 +/- 1 mV; n = 22). The raised PD principally reflected an increase in the rate of active transport (equivalent short circuit, Ieq) for CF epithelia (61 +/- 9 microA cm-2) as compared with normal epithelia (23 +/- 3 microA cm-2). No significant differences in transepithelial resistance were detected. 3. As indicated by ion replacement studies (gluconate for Cl-), the apical membrane of normal cells exhibits an apical membrane Cl- conductance (GCl) that can be activated by isoprenaline. CF cells do not exhibit an apical membrane GCl, nor can a GCl be activated by isoprenaline. 4. CF cells exhibited a larger amiloride-sensitive Ieq and amiloride-sensitive apical membrane conductance (GNa) than normal cells. Further, the amiloride-sensitive Ieq was increased by isoprenaline in CF but not normal airway epithelia. 5. Equivalent circuit analysis yielded evidence for a more positive electromotive force (EMF) across the apical membrane and a more negative EMF across the basolateral membrane of CF cells as compared with normal cells. Baseline resistances of the apical (Ra) and basolateral (Rb) membranes did not dif...