Characterization of cAMP dependent CFTR‐chloride channels in human trache gland cells

FEBS Letters

Figarella, C.²  Becq, F.¹  Voelckel, M.A.³  Merten, M.D.²  Gola, M.¹ 

[1] Laboratoire de Neurobiologie Cellulaire, CNRS, LNB4, 31 Chemin J. Aiguier, 13402 Marseille cedex 09, France;Groupe de Recherche sur les Glandes Exocrines, 27, Bld Lei Roure, 13273 Marseille cedex 09, France;INSERM U 242/CERGM, 27, Bld J. Moulin, 13005 Marseille, France

关键词: Human tracheal gland cell;    CFTR;    Chloride channel;    Patch-clamp;   

DOI  :  10.1016/0014-5793(93)80624-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Human tracheal gland cells are believed to be a major site at the origin of cystic fibrosis. Since this disease is due to mutations in a protein called CFTR, we looked for the activity of CFTR in human tracheal gland cells in culture. We have identified CFTR-like chloride-selective channels as having a linear current-voltage relationship and unitary conductance of 7 pS in these cells. In cell-attached patches, theophylline (1 mM), IBMX (1 mM), or a cocktail of dibutyryl cAMP (1 mM) and IBMX (0.1 mM) promoted the opening of channels. The unitary current had a reversal potential close to the cell resting potential. Replacement of choline by K⁺ or Na⁺ in the pipette solution was without effect on the current-voltage relationship, the reversal potential or the unitary conductance, which is consistent with the chloride selectivity of the channel. Channels were always found clustered and their opening probability was not noticeably dependent on membrane potential. This work therefore represents the first observation of a CFTR-like channel activity in submucosal gland cells.

【 授权许可】

Unknown