Acta physiologica Scandinavica
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Acta Physiol. Scand. · Dec 2005
Ion channel regulation of the dynamical instability of the resting membrane potential in saccular hair cells of the green frog (Rana esculenta).
We investigated the ion channel regulation of the resting membrane potential of hair cells with the aim to determine if the resting membrane potential is poised close to instability and thereby a potential cause of the spontaneous afferent spike activity. ⋯ Two intrinsic dynamical instabilities of V(m) are present in hair cells. One of these is observed as spontaneous voltage fluctuations by currents through K(IR), K(V) and h-channels in combination with a steady current through MET channels. The other instability shows as regenerative voltage changes involving Ca2+ and K(V) channels. The BK(Ca) channels prevent the spontaneous voltage fluctuations from activating the regenerative system.