Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
2004-3-22
pubmed:abstractText
Although cell culture studies have implicated the presence of vesicle proteins in mediating the release of glutamate from astrocytes, definitive proof requires the identification of the glutamate release mechanism and the localization of this mechanism in astrocytes at synaptic locales. In cultured murine astrocytes we show an array of vesicle proteins, including SNARE proteins, and vesicular glutamate transporters that are required to fill vesicles with glutamate. Using immunocytochemistry and single-cell multiplex reverse transcription-PCR we demonstrate the presence of these proteins and their transcripts within astrocytes freshly isolated from the hippocampus. Moreover, immunoelectron microscopy demonstrates the presence of VGLUT1 in processes of astrocytes of the hippocampus. To determine whether calcium-dependent glutamate release is mediated by exocytosis, we expressed the SNARE motif of synaptobrevin II to prevent the formation of SNARE complexes, which reduces glutamate release from astrocytes. To further determine whether vesicular exocytosis mediates calcium-dependent glutamate release from astrocytes, we performed whole cell capacitance measurements from individual astrocytes and demonstrate an increase in whole cell capacitance, coincident with glutamate release. Together, these data allow us to conclude that astrocytes in situ express vesicle proteins necessary for filling vesicles with the chemical transmitter glutamate and that astrocytes release glutamate through a vesicle- or fusion-related mechanism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12724-33
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:14722063-Amino Acid Motifs, pubmed-meshheading:14722063-Animals, pubmed-meshheading:14722063-Astrocytes, pubmed-meshheading:14722063-Blotting, Western, pubmed-meshheading:14722063-Brain, pubmed-meshheading:14722063-Calcium, pubmed-meshheading:14722063-Cells, Cultured, pubmed-meshheading:14722063-Electrophysiology, pubmed-meshheading:14722063-Exocytosis, pubmed-meshheading:14722063-Glutamic Acid, pubmed-meshheading:14722063-Hippocampus, pubmed-meshheading:14722063-Immunohistochemistry, pubmed-meshheading:14722063-Membrane Proteins, pubmed-meshheading:14722063-Mice, pubmed-meshheading:14722063-Mice, Transgenic, pubmed-meshheading:14722063-Microscopy, Electron, pubmed-meshheading:14722063-Microscopy, Fluorescence, pubmed-meshheading:14722063-Microscopy, Immunoelectron, pubmed-meshheading:14722063-Protein Structure, Tertiary, pubmed-meshheading:14722063-R-SNARE Proteins, pubmed-meshheading:14722063-RNA, Messenger, pubmed-meshheading:14722063-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:14722063-SNARE Proteins, pubmed-meshheading:14722063-Synapses, pubmed-meshheading:14722063-Time Factors, pubmed-meshheading:14722063-Vesicular Transport Proteins
pubmed:year
2004
pubmed:articleTitle
Fusion-related release of glutamate from astrocytes.
pubmed:affiliation
Department of Neuroscience, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't