Pflügers Archiv

, Volume 415, Issue 5, pp 617–623

Identification of a voltage- and calcium-dependent non-selective cation channel in cultured adult and fetal human nasal epithelial cells

  • Mark Jorissen
  • Johan Vereecke
  • Edward Carmeliet
  • Herman Van den Berghe
  • Jean -Jacques Cassiman
Transport Processes, Metabolism and Endocrinology; Kidney, Gastrointestinal Tract, and Exocrine Glands

DOI: 10.1007/BF02583515

Cite this article as:
Jorissen, M., Vereecke, J., Carmeliet, E. et al. Pflugers Arch. (1990) 415: 617. doi:10.1007/BF02583515
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Abstract

The apical membranes of cultured human nasal epithelial cells from adults and fetuses were investigated with the patch-clamp technique. Amiloride-insensitive, calcium- and voltage-dependent, non-selective cation channels were found in 4% of the cell-attached, and 18% of the inside-out and outside-out patches (n=412). Multiple functional channels were present in more than 90% of these patches, with a mean of 3.9 channels per patch (n=55). The current-voltage relationship can be described by the Goldman equations and the single channel conductance was 20.1±0.3 pS (n=29) in adult and 20.7±0.4 pS (n=44) in fetal cells in symmetrical 150mM NaCl solutions. The channels were highly selective for cations: PNa/PCl was 30 in adult and 45 in fetal experiments. They were equally permeable for K+ and Na+, somewhat less for Cs+, and impermeable for choline+ and tetraethylammonium+. The open probability was voltage dependent: it increased approximately 2-fold with 30mV depolarization in the potential range from −60mV to +60mV. The channels were activated by Ca2+ concentrations of about 10−4M at the cytoplasmic side, but were insensitive to extracellular Ca2+ and amiloride (10−4M). The non-selective cation channels found in apical membranes of cultured fetal nasal epithelial cells were not different from the adult ones.

Key words

Patch-clampNon-selective cation channelsCa2+ dependenceVoltage dependenceCultureFetal nasal epitheliumAdult nasal epithelium

Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • Mark Jorissen
    • 1
    • 3
  • Johan Vereecke
    • 2
  • Edward Carmeliet
    • 2
  • Herman Van den Berghe
    • 1
  • Jean -Jacques Cassiman
    • 1
  1. 1.Center for Human GeneticsUniversity of LeuvenLeuvenBelgium
  2. 2.Laboratory of PhysiologyUniversity of LeuvenLeuvenBelgium
  3. 3.ENT DepartmentUniversity of LeuvenLeuvenBelgium