Linked Life Data

11466454

Source:http://linkedlifedata.com/resource/pubmed/id/11466454

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
2001-7-23
pubmed:abstractText
Distinct interneuron populations innervate perisomatic and dendritic regions of cortical cells. Perisomatically terminating GABAergic inputs are effective in timing postsynaptic action potentials, and basket cells synchronize each other via gap junctions combined with neighboring GABAergic synapses. The function of dendritic GABAergic synapses in cortical rhythmicity, and their interaction with electrical synapses is not understood. Using multiple whole-cell recordings in layers 2-3 of rat somatosensory cortex combined with light and electron microscopic determination of sites of interaction, we studied the interactions between regular spiking nonpyramidal cells (RSNPCs). Random samples of unlabeled postsynaptic targets showed that RSNPCs placed GABAergic synapses onto dendritic spines (53 +/- 12%) and shafts (45 +/- 10%) and occasionally somata (2 +/- 4%). GABAergic interactions between RSNPCs were mediated by 4 +/- 2 axodendritic synapses and phased postsynaptic activity at beta frequency but were ineffective in phasing at gamma rhythm. Electrical interactions of RSNPCs were transmitted via two to eight gap junctions between dendritic shafts and/or spines. Elicited at beta and gamma frequencies, gap junctional potentials timed postsynaptic spikes with a phase lag, however strong electrical coupling could synchronize presynaptic and postsynaptic activity. Combined unitary GABAergic and gap junctional connections of moderate strength produced beta and gamma frequency synchronization of the coupled RSNPCs. Our results provide evidence that dendritic GABAergic and/or gap junctional mechanisms effectively transmit suprathreshold information in a population of interneurons at behaviorally relevant frequencies. A coherent network of GABAergic cells targeting the dendrites could provide a pathway for rhythmic activity spatially segregated from perisomatic mechanisms of synchronization.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5824-31
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Beta and gamma frequency synchronization by dendritic gabaergic synapses and gap junctions in a network of cortical interneurons.
pubmed:affiliation
Department of Comparative Physiology, University of Szeged, Szeged H-6726, Hungary.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't