Publication
Title
channels contribute to the delayed rectifier current in small cultured mouse dorsal root ganglion neurons
Author
Abstract
fBocksteins E, Van de Vijver G, Van Bogaert PP, Snyders DJ. K(V)3 channels contribute to the delayed rectifier current in small cultured mouse dorsal root ganglion neurons. Am J Physiol Cell Physiol 303: C406-C415, 2012. First published June 6, 2012; doi:10.1152/ajpcell.00343.2011.-Delayed rectifier voltage-gated K+ (K-V) channels are important determinants of neuronal excitability. However, the large number of K-V subunits poses a major challenge to establish the molecular composition of the native neuronal K+ currents. A large part (similar to 60%) of the delayed rectifier current (I-K) in small mouse dorsal root ganglion (DRG) neurons has been shown to be carried by both homotetrameric K(V)2.1 and heterotetrameric channels of K(V)2 subunits with silent K-V subunits (KVS), while a contribution of K(V)1 channels has also been demonstrated. Because K(V)3 subunits also generate delayed rectifier currents, we investigated the contribution of K(V)3 subunits to I-K in small mouse DRG neurons. After stromatoxin (ScTx) pretreatment to block the K(V)2-containing component, application of 1 mM TEA caused significant additional block, indicating that the ScTx-insensitive part of I-K could include K(V)1, K(V)3, and/or M-current channels (KCNQ2/3). Combining ScTx and dendrotoxin confirmed a relevant contribution of K(V)2 and K(V)2/KVS, and K(V)1 subunits to I-K in small mouse DRG neurons. After application of these toxins, a significant TEA-sensitive current (similar to 19% of total I-K) remained with biophysical properties that corresponded to those of K(V)3 currents obtained in expression systems. Using RT-PCR, we detected K(V)3.1-3 mRNA in DRG neurons. Furthermore, Western blot and immunocytochemistry using K(V)3.1-specific antibodies confirmed the presence of K(V)3.1 in cultured DRG neurons. These biophysical, pharmacological, and molecular results demonstrate a relevant contribution (similar to 19%) of K(V)3-containing channels to I-K in small mouse DRG neurons, supporting a substantial role for K(V)3 subunits in these neurons.
Language
English
Source (journal)
American journal of physiology: cell physiology. - Bethesda, Md
Publication
Bethesda, Md : 2012
ISSN
0363-6143
Volume/pages
303:4(2012), p. C406-C415
ISI
000307804800007
Full text (Publishers DOI)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 09.10.2012
Last edited 13.04.2017
To cite this reference