Involvement of actin cytoskeleton in modulation of Ca2+-activated K+ channels from rat hippocampal CA1 pyramidal neurons

doi:10.1016/S0304-3940(02)00836-4

Neuroscience Letters

Volume 332, Issue 2, 31 October 2002, Pages 141-145

https://doi.org/10.1016/S0304-3940(02)00836-4 Get rights and content

Abstract

Using inside-out configuration of patch clamp techniques, actin cytoskeleton modulation of large conductance calcium-activated potassium (BK_Ca) channels was studied in hippocampal CA1 pyramidal neurons from adult rat. Disruption of actin filament after brief treatment with cytochalasin D (CD) markedly decreased activity of BK_Ca channels and this inhibitory action persisted even after CD washout. This CD-produced decrease in BK_Ca channel activity was characterized by a shortened open lifetime and reduced opening frequency. Disruption of actin filament with another toxin cytochalasin B also exerted similar effects as CD. Phalloidin, the actin filament stabilizer, had no significant effect on BK_Ca channel activity, while pre-treatment with phalloidin could prevent the CD-induced inhibitory effect on channel activity. The present study demonstrates that disruption of actin cytoskeleton can inhibit BK_Ca channel activity, suggesting that BK_Ca channels in rat hippocampal CA1 pyramidal neurons may be directly modulated by dynamic assembly and disassembly of submembranous actin cytoskeleton.

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¹: These authors contribute equally to this paper.

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Involvement of actin cytoskeleton in modulation of Ca2+-activated K+ channels from rat hippocampal CA1 pyramidal neurons

Abstract

Exp. Neurol.

Neuron

J. Biol. Chem.

Curr. Opin. Neurobiol.

Role of actin in anchoring postsynaptic receptors in cultured hippocampal neurons: differential attachment of NMDA versus AMPA receptors

J. Neurosci.

Actions of cytochalasins on the organization of actin filaments and microtubules in neuronal growth core

J. Cell Biol.

Properties of large conductance calcium-activated potassium channels in pyramidal neurons from the hippocampal CA1 region of adult rats

Jpn. J. Physiol.

Transient forebrain ischemia induces persistent hyperactivity of large conductance Ca2+-activated potassium channels via oxidation modulation in rat hippocampal CA1 pyramidal neurons

Eur. J. Neurosci.

The role of the cytoskeleton in hormone action

Can. J. Biochem. Cell Biol.

Improved patch clamp techniques for high-resolution current recording from cells and cell-free membrane patches

Pflugers Arch.

Involvement of actin cytoskeleton in modulation of Ca²⁺-activated K⁺ channels from rat hippocampal CA1 pyramidal neurons

Transient forebrain ischemia induces persistent hyperactivity of large conductance Ca²⁺-activated potassium channels via oxidation modulation in rat hippocampal CA1 pyramidal neurons