Potassium channels in colonic crypts.

G I Sandle; C M McNicholas; R B Lomax

doi:10.1016/s0140-6736(94)90878-8

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PubMed · 7905044

Potassium channels in colonic crypts.

G I Sandle·C M McNicholas·R B Lomax

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Abstract

A characteristic feature of intestinal epithelia is their ability to secrete chloride (Cl-), a process that occurs mainly in intestinal crypts and is the critical transport event in secretory diarrhoea. Increased potassium (K+) channel activity in the basolateral membrane has an important role in the Cl- secretory process by hyperpolarising the cell and maintaining a favourable electrochemical driving force for Cl- exit at the apical membrane. We have shown, using patch-clamp techniques, that the basolateral membrane of human colonic crypt cells contains low conductance K+ channels that are voltage and calcium (Ca2+) sensitive and blocked by barium (Ba2+). These K+ channels are regulated by cytosolic cyclic adenosine monophosphate (cAMP) and Ca2+, intracellular second messengers that also stimulate Cl- secretion. This population of human intestinal K+ channels may be a target for the pharmacological control of Cl- secretory diarrhoea.

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Bucladesine Calcium Channels Carbachol Chlorides Colon Diarrhea Electrophysiology Humans In Vitro Techniques Intestinal Mucosa Ion Transport Potassium Channels Journal Article Research Support, Non-U.S. Gov't

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G I Sandle, C M McNicholas, R B Lomax. 1994-01-01. Potassium channels in colonic crypts.. https://doi.org/10.1016/s0140-6736(94)90878-8

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