Linked Life Data

16775204

Source:http://linkedlifedata.com/resource/pubmed/id/16775204

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2006-8-10
pubmed:abstractText
Gap junction communication between astrocytes is prevalent and has been proposed to be involved in several astrocyte functions. One such proposal involves gap junctions in potassium spatial buffering. However, little is known about the developmental time course of gap junction coupling and how much the syncytium affects whole cell measurements of ion currents. Our previous work described three types of hippocampal astrocyte, each with a distinct electrophysiological profile when recorded in whole cell voltage-clamp mode. In the current study we correlated post-whole cell recording immunohistochemistry for GLAST and the spread of injected dye from the recorded cell with the measured electrophysiological phenotype to quantify cell coupling of astrocytes and the type of astrocyte coupled, in the rat hippocampus. We found that passive astrocytes, which predominate after 3 wk postnatally, have much lower membrane resistances (Rm) and are more frequently dye coupled and to more cells, than outwardly and variably rectifying astrocytes that predominate in early postnatal development. Dye coupling in GLAST(+) cells was first detected in the first postnatal week and the degree of coupling peaked before the complete transition to the low Rm, passive electrophysiological type. Also, the degree of dye coupling did not correlate with the passive electrophysiological phenotype. Passive cells were also detected after pretreatment with a gap junction inhibitor. Further evidence that cell coupling does not contribute to the mature astrocyte electrophysiological phenotype came from recording of excised membrane patches, which predominantly corresponded to the ion channel expression profiles of their cells of origin. These findings imply that in the hippocampus, interastrocyte cell coupling likely contributes little to the overall whole cell current profile of diverse glia, and the electrophysiological passivity reflects the intrinsic ion channel expression of the mature astrocyte.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
96
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1383-92
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Development of gap junctions in hippocampal astrocytes: evidence that whole cell electrophysiological phenotype is an intrinsic property of the individual cell.
pubmed:affiliation
Neural and Vascular Biology Theme, Ordway Research Institute, Inc., Albany, NY 12208, USA. gschools@ordwayresearch.org
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't