Linked Life Data

20600663

Source:http://linkedlifedata.com/resource/pubmed/id/20600663

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-8-9
pubmed:abstractText
The presence of large-conductance Ca(2+)-activated potassium (BK) channels, which are considered to play an important role in the excitability of neurons, in the highly-excitable lateral globus pallidus (LGP) neurons has yet to be confirmed. In this study, we confirmed the functional expression of BK channels in mouse LGP neurons and investigated the characteristics of their single-channel currents using inside-out patch-clamp recordings. These BK channels had a conductance of 276 pS, were activated by the elevation of both the transmembrane potential and intracellular calcium concentration ([Ca(2+)](i)), and were completely blocked by the BK channel-specific blocker paxilline (100 nM). In addition, the channel currents were sensitive to high-energy phosphate compounds and low internal pH. The cellular function of these BK channels was then investigated by nystatin-perforated whole-cell recording. Paxilline (100 nM) had no effect on the frequency and half-width of the action potential (AP) in LGP neurons under control conditions, but significantly attenuated the hyperpolarization that was caused by carbonyl cyanide m-chlorophenylhydrazone (CCCP), an inhibitor of ATP synthesis. In addition, the pancreatic beta-cell type ATP-sensitive potassium channel (K(ATP) channel) blocker tolbutamide (0.25 mM) also attenuated the hyperpolarization, in a manner similar to paxilline. The voltage-dependent potassium channel blocker tetraethylammonium (TEA, 2 mM) significantly decreased the frequency and increased the half-width of the AP in LGP neurons under control conditions, and attenuated CCCP-induced hyperpolarization to an extent close to that of paxilline. The results presented here suggest that functional BK channels are present in LGP neurons, and may behave as partners of K(ATP) channels in the regulation of neuronal activity under metabolic stress conditions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1873-7544
pubmed:author
pubmed:copyrightInfo
(c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
169
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1548-56
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Functional expression of large-conductance Ca2+-activated potassium channels in lateral globus pallidus neurons.
pubmed:affiliation
State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, PR China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't