Linked Life Data

11495932

Source:http://linkedlifedata.com/resource/pubmed/id/11495932

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2001-8-9
pubmed:abstractText
Using whole cell patch-clamp recording from hypoglossal motoneurons of a neonatal rat brain slice preparation, we investigated short-term changes in synaptic transmission mediated by GABA or glycine. In 1.5 mM extracellular Ca(2+) [Ca(2+)](o), pharmacologically isolated GABAergic or glycinergic currents were elicited by electrical stimulation of the reticular formation. At low stimulation frequency, glycinergic currents were larger and faster than GABAergic ones. GABAergic currents were strongly facilitated by pulse trains at 5 or 10 Hz without apparent depression. This phenomenon persisted after pharmacological block of GABA(B) receptors. Glycinergic currents were comparatively much less enhanced than GABAergic currents. One possible mechanism to account for this difference is that GABAergic currents decayed so slowly that consecutive responses summated over an incrementing baseline. However, while synaptic summation appeared at > or =10-Hz stimulation, at 5 Hz strong facilitation developed with minimal summation of GABA-mediated currents. Glycinergic currents decayed so fast that summation was minimal. As [Ca(2+)](o) is known to shape short-term synaptic changes, we examined if varying [Ca(2+)](o) could differentially affect facilitation of GABA- or glycine-operated synapses. With 5 mM [Ca(2+)](o), the frequency of spontaneous GABAergic or glycinergic currents appeared much higher but GABAergic current facilitation was blocked (and replaced by depression), whereas glycinergic currents remained slightly facilitated. [Ca(2+)](o) manipulation thus brought about distinct processes responsible for facilitation of GABAergic or glycinergic transmission. Our data therefore demonstrate an unexpectedly robust, short-term increase in the efficiency of GABAergic synapses that can become at least as effective as glycinergic synapses.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-3077
pubmed:author
pubmed:issnType
Print
pubmed:volume
86
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
565-74
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Differential short-term changes in GABAergic or glycinergic synaptic efficacy on rat hypoglossal motoneurons.
pubmed:affiliation
Biophysics Sector and Istituto Nazionale di Fisica della Materia Unit, International School for Advanced Studies (SISSA), 34014 Trieste, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't