Epithelial Na channels: the nature of the conducting pore
- PMID: 1689861
- DOI: 10.1159/000173347
Epithelial Na channels: the nature of the conducting pore
Abstract
Na-selective, amiloride-sensitive ion channels are a crucial component of the system for controlled NaCl reabsorption across tight epithelia. A kinetic model for the process of Na conduction through the channel is presented. The model is based on a view of the possible geometry of the pore obtained from an analysis of voltage-dependent block of Na currents by impermeant cations. It is also consistent with the known electrophysiological properties of the channel, including single-channel currents, current-voltage relationships and saturation. The model, while not a unique explanation of the available data, may serve as a starting point for more detailed experimental and theoretical studies.
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