Linked Life Data

21106816

Source:http://linkedlifedata.com/resource/pubmed/id/21106816

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
47
pubmed:dateCreated
2010-11-25
pubmed:abstractText
The K(ir)4.1 channel is crucial for the maintenance of the resting membrane potential of glial cells, and it is believed to play a main role in the homeostasis of extracellular potassium. To understand its importance in these two phenomena, we have measured in vivo the variations of extracellular potassium concentration ([K(+)](o)) (with potassium-sensitive microelectrodes) and membrane potential of glial cells (with sharp electrodes) during stimulations in wild-type (WT) mice and glial-conditional knock-out (cKO) K(ir)4.1 mice. The conditional knockout was driven by the human glial fibrillary acidic protein promoter, gfa2. Experiments were performed in the hippocampus of anesthetized mice (postnatal days 17-24). Low level stimulation (<20 stimuli, 10 Hz) induced a moderated increase of [K(+)](o) (<2 mm increase) in both WT and cKO mice. However, cKO mice exhibited slower recovery of [K(+)](o) levels. With long-lasting stimulation (300 stimuli, 10 Hz), [K(+)](o) in WT and cKO mice displayed characteristic ceiling level (>2 mm increase) and recovery undershoot, with a more pronounced and prolonged undershoot in cKO mice. In addition, cKO glial cells were more depolarized, and, in contrast to those from WT mice, their membrane potential did not follow the stimulation-induced [K(+)](o) changes, reflecting the loss of their high potassium permeability. Our in vivo results support the role of K(ir)4.1 in setting the membrane potential of glial cells and its contribution to the glial potassium permeability. In addition, our data confirm the necessity of the K(ir)4.1 channel for an efficient uptake of K(+) by glial cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
24
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
15769-77
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Implication of Kir4.1 channel in excess potassium clearance: an in vivo study on anesthetized glial-conditional Kir4.1 knock-out mice.
pubmed:affiliation
Department of Stomatology, Université de Montréal, Montréal, Québec H3T 1J4, Canada.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't