Apical and basolateral membrane ionic channels in rabbit urinary bladder epithelium.

S A Lewis; J W Hanrahan

doi:10.1007/bf00581785

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PubMed · 2418408

Apical and basolateral membrane ionic channels in rabbit urinary bladder epithelium.

S A Lewis·J W Hanrahan

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Abstract

This paper reviews the properties and regulation of single amiloride-sensitive Na+ channels in the apical membrane, and Cl- and K+ channels in the basolateral membrane of rabbit urinary bladder. According to fluctuation analysis, there is an average of one amiloride-sensitive Na+ channel for every 40 micron2 of apical membrane. Each Na+ channel passes 0.7 pA of current under normal, short-circuit conditions. Apical channels are hydrolysed by the endogenous enzyme urokinase, which is released into the urine by the kidney. After exposure to urokinase, the Na+ channel loses its amiloride sensitivity, and eventually becomes unstable in the membrane. The selectivity and kinetic properties of single anion and K+ channels in the basolateral membrane were also studied using the patch clamp technique. The properties of these channels are discussed in terms of the regulation of transepithelial Na+ transport.

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Amiloride Animals Cell Membrane Chlorides Epithelium Ion Channels Mathematics Models, Biological Potassium Rabbits Sodium Urinary Bladder Urokinase-Type Plasminogen Activator Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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S A Lewis, J W Hanrahan. 1985. Apical and basolateral membrane ionic channels in rabbit urinary bladder epithelium.. https://doi.org/10.1007/bf00581785

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