Open AccessFunction of proton channels in lung epithelia
Author(s) -
Fischer Horst
Publication year - 2011
Publication title -
wiley interdisciplinary reviews: membrane transport and signaling
Language(s) - English
Resource type - Journals
eISSN - 2190-4618
pISSN - 2190-460X
DOI - 10.1002/wmts.17
Subject(s) - extracellular , intracellular , epithelial sodium channel , lung , intracellular ph , chemistry , epithelium , biophysics , apical membrane , membrane potential , microbiology and biotechnology , secretion , depolarization , biochemistry , membrane , medicine , biology , sodium , genetics , organic chemistry
The properties of the voltage‐dependent H + channel have been studied in lung epithelial cells for many years, and recently voltage‐dependent H + channel 1 (HVCN1) messenger RNA expression has been linked directly to H + channel function in lung epithelium. The H + channel is activated by strong membrane depolarization, intracellular acidity, or extracellular alkalinity. Early on it was noted that these are surprising physiological channel characteristics when considering that lung epithelial cells have rather stable membrane potentials and a well pH‐buffered intracellular milieu. This raised the question under which conditions the H + channel is active in lung epithelium and what is its physiological function there. Current understanding of the HVCN1 H + channel in lung epithelial acid secretion, its activation by an alkaline mucosal extracellular pH, and its role in the regulation of the mucosal pH of the lung has resulted in a model of mucosal pH regulation based on the parallel function of the HVCN1 H + channel and the CFTR HCO 3 − channel, which suggests that HVCN1 is a critical factor that maintains a neutral surface pH in the lung. WIREs Membr Transp Signal 2012,1:247–258. doi: 10.1002/wmts.17 For further resources related to this article, please visit the WIREs website .