Linked Life Data

18442094

Source:http://linkedlifedata.com/resource/pubmed/id/18442094

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2008-6-16
pubmed:abstractText
GABA (gamma-aminobutyric acid) is a transmitter with dual action. Whereas it excites neurons during the first week of postnatal development, it represents the major inhibitory transmitter in the mature brain. GABA also activates astrocytes by binding to ionotropic (GABA(A)) and metabotropic (GABA(B)) receptors. This results in glial calcium transients which can induce the release of gliotransmitters, rendering GABA an important mediator of neuron-glia interaction. Using whole-cell patch-clamp and ratiometric calcium imaging in hippocampal slices from rats at postnatal days 3-34, we have analyzed the developmental profile as well as the cellular mechanisms of calcium signals induced by GABA(A) and GABA(B) receptor activation in astrocytes. We found that GABA-evoked glial calcium transients are mediated by both GABA(A) and GABA(B) receptors. Throughout development, GABA(A)-receptor activation resulted in immediate calcium transients in the vast majority of astrocytes, most likely by influx of calcium through voltage-gated calcium channels. GABA(B) receptor activation, in contrast, resulted in delayed calcium transients, which were blocked following depletion of intracellular calcium stores and during persistent activation of heterotrimeric G-proteins. GABA(B) receptor-mediated calcium signals exhibited a clear developmental profile with less than 10% of astrocytes responding at P3 or P32-34, and about 60% of cells between P11 and P15. Our data thus indicate that GABA(B) receptor-mediated calcium transients are due to calcium release from intracellular stores following G-protein activation. Moreover, GABA(B) receptor-mediated calcium signaling in astrocytes preferentially occurs at a period during postnatal development when hippocampal networks are established.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1098-1136
pubmed:author
pubmed:copyrightInfo
(c) 2008 Wiley-Liss, Inc.
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1127-37
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Developmental profile and mechanisms of GABA-induced calcium signaling in hippocampal astrocytes.
pubmed:affiliation
Institute for Neurobiology, Heinrich-Heine-University of Duesseldorf, Universitaetsstrasse 1, Duesseldorf, Germany.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, Non-U.S. Gov't