Linked Life Data

16943315

Source:http://linkedlifedata.com/resource/pubmed/id/16943315

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2007-3-13
pubmed:abstractText
Recent experimental and modeling results demonstrated that surviving mossy cells in the dentate gyrus play key roles in the generation of network hyperexcitability. Here we examined if mossy cells exhibit long-term plasticity in the posttraumatic, hyperexcitable dentate gyrus. Mossy cells 1 wk after fluid percussion head injury did not show alterations in their current-firing frequency (I-F) and current-membrane voltage (I-V) relationships. In spite of the unchanged I-F and I-V curves, mossy cells showed extensive modifications in Na(+), K(+) and h-currents, indicating the coordinated nature of these opposing modifications. Computational experiments in a realistic large-scale model of the dentate gyrus demonstrated that individually, these perturbations could significantly affect network activity. Synaptic inputs also displayed systematic, opposing modifications. Miniature excitatory postsynaptic current (EPSC) amplitudes were decreased, whereas miniature inhibitory postsynaptic current (IPSC) amplitudes were increased as expected from a homeostatic response to network hyperexcitability. In addition, opposing alterations in miniature and spontaneous synaptic event frequencies and amplitudes were observed for both EPSCs and IPSCs. Despite extensive changes in synaptic inputs, cannabinoid-mediated depolarization-induced suppression of inhibition was not altered in posttraumatic mossy cells. These data demonstrate that many intrinsic and synaptic properties of mossy cells undergo highly specific, long-term alterations after traumatic brain injury. The systematic nature of such extensive and opposing alterations suggests that single-cell properties are significantly influenced by homeostatic mechanisms in hyperexcitable circuits.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
97
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2394-409
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed-meshheading:16943315-Animals, pubmed-meshheading:16943315-Animals, Newborn, pubmed-meshheading:16943315-Computer Simulation, pubmed-meshheading:16943315-Craniocerebral Trauma, pubmed-meshheading:16943315-Disease Models, Animal, pubmed-meshheading:16943315-Dose-Response Relationship, Radiation, pubmed-meshheading:16943315-Drug Interactions, pubmed-meshheading:16943315-Electric Stimulation, pubmed-meshheading:16943315-Membrane Potentials, pubmed-meshheading:16943315-Models, Neurological, pubmed-meshheading:16943315-Mossy Fibers, Hippocampal, pubmed-meshheading:16943315-Nerve Net, pubmed-meshheading:16943315-Neurons, pubmed-meshheading:16943315-Patch-Clamp Techniques, pubmed-meshheading:16943315-Piperidines, pubmed-meshheading:16943315-Potassium Channel Blockers, pubmed-meshheading:16943315-Pyrazoles, pubmed-meshheading:16943315-Pyrimidines, pubmed-meshheading:16943315-Rats, pubmed-meshheading:16943315-Sodium Channel Blockers, pubmed-meshheading:16943315-Tetraethylammonium, pubmed-meshheading:16943315-Tetrodotoxin
pubmed:year
2007
pubmed:articleTitle
Opposing modifications in intrinsic currents and synaptic inputs in post-traumatic mossy cells: evidence for single-cell homeostasis in a hyperexcitable network.
pubmed:affiliation
Department of Anatomy and Neurobiology, University of California, Irvine, CA 92697, USA. ahoward@uci.edu
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural