Linked Life Data

16338906

Source:http://linkedlifedata.com/resource/pubmed/id/16338906

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2006-2-13
pubmed:abstractText
The purinergic P2X(7) receptor (P2X(7)R) can mediate glutamate release from cultured astrocytes. Using patch clamp recordings, we investigated whether P2X(7)Rs have the same action in hippocampal astrocytes in situ. We found that 2- and 3-O-(4-benzoylbenzoyl)ATP (BzATP), a potent, although unselective P2X(7)R agonist, triggers two different glutamate-mediated responses in CA1 pyramidal neurons; they are transient inward currents, which have the kinetic and pharmacological properties of previously described slow inward currents (SICs) due to Ca(2+)-dependent glutamate release from astrocytes, and a sustained tonic current. Although SICs were unaffected by P2X(7)Rs antagonists, the tonic current was inhibited, was amplified in low extracellular Ca(2+), and was insensitive to glutamate transporter and hemichannel inhibitors. BzATP triggered in astrocytes a large depolarization that was inhibited by P2X(7)R antagonists and amplified in low Ca(2+). In low Ca(2+) BzATP also induced lucifer yellow uptake into a subpopulation of astrocytes and CA3 neurons. Our results demonstrate that purinergic receptors other than the P2X(7)R mediate glutamate release that evokes SICs, whereas activation of a receptor that has features similar to the P2X(7)R, mediates a sustained glutamate efflux that generates a tonic current in CA1 neurons. This sustained glutamate efflux, which is potentiated under non-physiological conditions, may have important pathological actions in the brain.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
281
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4274-84
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Purinergic receptors mediate two distinct glutamate release pathways in hippocampal astrocytes.
pubmed:affiliation
Consiglio Nazionale delle Ricerche Istituto di Neuroscienze and Dipartimento di Scienze Biomediche Sperimentali, Università di Padova, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't