Linked Life Data

9325348

Source:http://linkedlifedata.com/resource/pubmed/id/9325348

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1997-11-13
pubmed:abstractText
A presynaptic voltage-control method was used to study synaptic facilitation at the inhibitory neuromuscular synapse of the crayfish opener muscle. The expression of the F2 component of facilitation, monitored 150 ms after a conditioning stimulus, was examined by systematically changing the duration of the presynaptic test pulse. (Test pulses in all experiments were depolarized to 0 mV.) Control and facilitated inhibitory postsynaptic potentials (IPSPs) exhibited identical time courses when test pulse duration was brief (approximately 2 ms). When the duration of the test pulse was increased beyond 2 ms, the transmitter release time course shifted to an earlier point in time during facilitation. Meanwhile, the increase in total transmitter release, measured from inhibitory postsynaptic conductance (IPSG) area (total release), became less pronounced with increasing duration of the test pulse. With a 20-ms test pulse, facilitation did not cause any detectable change in total release but the half-maximal point of the facilitated IPSG shifted by 3 ms (release shift). This change in release kinetics was not associated with a decrease in minimal synaptic delay. Furthermore, the relationship between total release and presynaptic pulse duration suggested that the transmitter release activated by a 20-ms pulse can be defined as a distinct component of continuous transmitter release (early component). The facilitation process accelerated the release kinetics of the early component but did not modify its total transmitter content. To test the hypothesis that the release shift is indeed mediated by the same mechanism that increases IPSP amplitude during facilitation, we investigated the correlation between the release shift and IPSP amplitude change. The two parameters were significantly correlated when the magnitude of facilitation was changed 1) during the decay of facilitation and 2) by varying the strength of the conditioning stimulus. The experimental approach reported here provides two new physiological parameters, release shift and total release, for the analysis of synaptic facilitation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
78
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1791-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Change of transmitter release kinetics during facilitation revealed by prolonged test pulses at the inhibitor of the crayfish opener muscle.
pubmed:affiliation
Department of Biology, Boston University, Boston, Massachusetts 02215, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't