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PubMed · 1974057

ATP-sensitive K(+)-channel run-down is Mg2+ dependent.

R Z Kozlowski·M L Ashford
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Abstract

ATP-sensitive K(+)-channel currents were recorded from isolated membrane patches and voltage-clamped CRI-G1 insulin-secreting cells. Internal Mg2+ ions inhibited ATP-K+ channels by a voltage-dependent block of the channel current and decrease of open-state probability. The run-down of ATP-K+ channel activity was also shown to be [Mg2+]i dependent, being almost abolished in Mg2(+)-free conditions. Substitution of Mn2+ for Mg2+ did not prevent run-down, nor did the presence of phosphate-donating nucleotides, a protease or phosphatase inhibitor or replacement of Cl- by gluconate.

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Adenosine TriphosphateAnimalsCell LineEgtazic AcidElectric ConductivityKineticsMagnesiumManganeseMembrane PotentialsPotassium ChannelsRatsJournal Article

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R Z Kozlowski, M L Ashford. 1990-06-22. ATP-sensitive K(+)-channel run-down is Mg2+ dependent.. https://doi.org/10.1098/rspb.1990.0044

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