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PubMed · 2420186

The amiloride-sensitive sodium channel.

S Sariban-Sohraby·D J Benos
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Abstract

Net Na+ movement across the apical membrane of high-electrical resistance epithelia is driven by the electrochemical potential energy gradient. This entry pathway is rate limiting for transepithelial transport, occurs via a channel-type mechanism, and is specifically inhibited by the diuretic drug amiloride. This channel is selective for Na+, Li+, and H+, saturates with increasing extracellular Na+ concentration, and is not affected, at least in frog skin epithelium, by changes in apical membrane surface potential. There also appears to be multiple inhibitory regions associated with each Na+ channel. We discuss the possible implications of a voltage-dependent block by amiloride in terms of macroscopic inhibitory phenomena. We describe the use of cultured epithelial systems, in particular, the toad kidney-derived A6 cell line, and the preparation of apical plasma membrane vesicles to study the Na+ entry process. We discuss experiments in which single, amiloride-sensitive channel activity has been detected and summarize current experimental approaches directed at the biochemical identification of this ubiquitous Na+ transport system.

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Affinity LabelsAldosteroneAmilorideAnimalsAntibodiesAnuraBiomechanical PhenomenaCarrier ProteinsCell MembraneElectric ConductivityElectrochemistryEpithelial CellsEpitheliumIon ChannelsLightModels, BiologicalSkinSodiumSodium RadioisotopesStructure-Activity RelationshipComparative StudyJournal ArticleResearch Support, U.S. Gov't, P.H.S.Review

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BibTeXRIS

S Sariban-Sohraby, D J Benos. 1986. The amiloride-sensitive sodium channel.. https://doi.org/10.1152/ajpcell.1986.250.2.c175

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