Referenced in: none

Automatically associated channels: SK3

Title: A functional role for small-conductance calcium-activated potassium channels in sensory pathways including nociceptive processes.

Authors: Parmvir K Bahia, Rie Suzuki, David C H Benton, Amanda J Jowett, Mao Xiang Chen, Derek J Trezise, Anthony H Dickenson, Guy W J Moss

Journal, date & volume: J. Neurosci., 2005 Apr 6 , 25, 3489-98

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/15814779

Abstract
We investigated the role of small-conductance calcium-activated potassium (SK) and intermediate-conductance calcium-activated potassium channels in modulating sensory transmission from peripheral afferents into the rat spinal cord. Subunit-specific antibodies reveal high levels of SK3 immunoreactivity in laminas I, II, and III of the spinal cord. Among dorsal root ganglion neurons, both peripherin-positive (C-type) and peripherin-negative (A-type) cells show intense SK3 immunoreactivity. Furthermore, dorsal root-stimulated sensory responses recorded in vitro are inhibited when SK channel activity is increased with 1-ethyl-2-benzimidazolinone (1-EBIO). In vivo electrophysiological recordings show that neuronal responses to naturally evoked nociceptive and nonnociceptive stimuli increase after application of the selective SK channel blocker 8,14-diaza-1,7(1,4)-diquinolinacyclotetradecaphanedium di-trifluoroacetate (UCL 1848), indicating that SK channels are normally active in moderating afferent input. Conversely, neuronal responses evoked by mechanical stimuli are inhibited when SK channel activity is increased with 1-EBIO. These effects are reversed by the subsequent application of UCL 1848. Our data demonstrate that SK channels have an important role in controlling sensory input into the spinal cord.