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Single-channel recording of ligand-gated ion channels

Nature Protocols volume 2, pages 2826–2841 (2007)Cite this article

Abstract

Electrophysiological recording of single-channel currents is the most direct method available for obtaining detailed and precise information about the kinetic behavior of ion channels. A wide variety of cell types can be used for single-channel recording, but to obtain the highest resolution of the briefest channel opening and closing events, low-noise recordings, coupled with a minimal filtering frequency, are required. Here, we present a protocol designed to help those with some electrophysiological expertise who wish to explore the properties of native and recombinant single ligand-gated ion channels. We have focused on the practical aspects of recording single GABA channels from cell-attached and outside-out patches and also introduced some of the preliminary considerations that are necessary for the analysis of single-channel data, including an introduction to single-channel analysis software.

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Figure 1: Schematic of single-channel bath chamber.
Figure 2: Clusters, bursts and individual channel openings.
Figure 3: Channel stacking and low versus subconductance levels.
Figure 4: Different idealization methods can lead to different results.
Figure 5: Amplitude histograms fitted with Gaussian functions.
Figure 6: Dwell-time histograms fitted with exponentials.

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Acknowledgements

We thank Marco Beato for comments on the manuscript and Guy Moss for discussion. This work was supported by MRC and the Alfred Benzon's Foundation.

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  1. Department of Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK

    Martin Mortensen & Trevor G Smart

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  1. Martin Mortensen
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Correspondence to Trevor G Smart.

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Mortensen, M., Smart, T. Single-channel recording of ligand-gated ion channels. Nat Protoc 2, 2826–2841 (2007). https://doi.org/10.1038/nprot.2007.403

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