Linked Life Data

14509565

Source:http://linkedlifedata.com/resource/pubmed/id/14509565

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2003-9-25
pubmed:abstractText
Inferior olivary neurons receive extensive glutamatergic and GABAergic innervation. Yet, because of the membrane properties of olivary neurons these neurotransmitters can produce only small changes in the firing rates of these cells. Moreover, olivary neurons can generate spontaneous spike activity in the absence of excitatory glutamatergic input. These facts suggest that glutamate and GABA have additional roles within the olivocerebellar system beyond simply modulating single cell firing probability. Indeed, one of the characteristics of the olivocerebellar system is its ability to generate synchronous complex spike activity across populations of Purkinje cells. The pattern of synchronous activity changes rapidly, and is thought to reflect the momentary distribution of effective electrotonic coupling between olivary neurons as shaped by afferent input to the inferior olive. However, it also possible that synchronous olivocerebellar activity is the result of synchrony inherent in the afferent activity itself. The issue of the origin of complex spike synchrony, and the role of glutamatergic olivary afferents in modulating its distribution were recently studied using multiple electrode recordings from Purkinje cells. The results of these studies, reviewed here, demonstrate that synchronous complex spike activity occurs in the absence of glutamatergic (and GABAergic) input to the inferior olive, and therefore indicate that synchronization of complex spike activity primarily results from the electrotonic coupling of olivary neurons, rather than from synchronization present within their afferents. Instead of triggering synchronous discharges directly, the results suggest that the function of tonic excitatory activity is to modulate the effective coupling of spike activity between olivary neurons. Blocking glutamate within the inferior olive causes an enhancement of the normal banding pattern of complex spike synchrony, with higher synchrony among parasagittally aligned Purkinje cells and less synchrony between non-aligned cells. This is in contrast to the more uniform synchrony distribution that follows block of GABAergic olivary afferents. Thus, GABA and glutamate play critical, and complementary, roles in determining the patterns of synchronous complex spike activity that are likely central to the functioning of the olivocerebellar system.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1473-4222
pubmed:author
pubmed:issnType
Print
pubmed:volume
2
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
165-70
pubmed:dateRevised
2011-9-22
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Excitatory afferent modulation of complex spike synchrony.
pubmed:affiliation
Department of Physiology & Neuroscience, New York University, School of Medicine, New York, New York 10016, USA. Lange01@popmail.med.nyu.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Review