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bioRxiv · 10.1101/2021.11.14.468518

Modeling Macroscopic Currents of Ion Channels

Wu, D.
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Abstract

Ion-channel functions are often studied by the current-voltage relation, which is commonly fitted by the Boltzmann equation, a powerful model widely used nowadays. However, the Boltzmann model is restricted to a two-state ion-permeation process. Here we present an improved model that comprises a flexible number of states and incorporates both the single-channel conductance and the open-channel probability. Employing the channel properties derived from the single-channel recording experiments, the proposed model is able to describe various current-voltage relations, especially the reversal ion-permeation curves showing the inward- and outward-rectifications. We demonstrate the applicability of the proposed model using the published patch-clamp data of BK and MthK potassium channels, and discuss the similarity of the two channels based on the model studies.

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Wu, D.. 2021-11-14. Modeling Macroscopic Currents of Ion Channels. https://doi.org/10.1101/2021.11.14.468518

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