Linked Life Data

11122337

Source:http://linkedlifedata.com/resource/pubmed/id/11122337

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2001-2-9
pubmed:abstractText
Long-term changes of synaptic transmission in slices of rat visual cortex were induced by intracellular tetanization: bursts of short depolarizing pulses applied through the intracellular electrode without concomitant presynaptic stimulation. Long-term synaptic changes after this purely postsynaptic induction were associated with alterations of release indices, thus providing a case for retrograde signalling at neocortical synapses. Both long-term potentiation and long-term depression were accompanied by presynaptic changes, indicating that retrograde signalling can achieve both up- and down-regulation of transmitter release. The direction and the magnitude of the amplitude changes induced by a prolonged intracellular tetanization depended on the initial properties of the input. The inputs with initially high paired-pulse facilitation (PPF) ratio, indicative of low release probability, were most often potentiated. The inputs with initially low PPF ratio, indicative of high release probability, were usually depressed or did not change. Thus, prolonged postsynaptic activity can lead to normalization of the weights of nonactivated synapses. The dependence of polarity of synaptic modifications on initial PPF disappeared when plastic changes were induced with a shorter intracellular tetanization, or when the NO signalling pathway was interrupted by inhibition of NO synthase activity or by application of NO scavengers. This indicates that the NO-dependent retrograde signalling system has a relatively high activation threshold. Long-term synaptic modifications, induced by a weak postsynaptic challenge or under blockade of NO signalling, were nevertheless associated with presynaptic changes. This suggests the existence of another retrograde signalling system, additional to the high threshold, NO-dependent system. Therefore, our data provide a clear case for retrograde signalling at neocortical synapses and indicate that multiple retrograde signalling systems, part of which are NO-dependent, are involved.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0953-816X
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4255-67
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11122337-Animals, pubmed-meshheading:11122337-Cyclic N-Oxides, pubmed-meshheading:11122337-Electric Stimulation, pubmed-meshheading:11122337-Excitatory Postsynaptic Potentials, pubmed-meshheading:11122337-Free Radical Scavengers, pubmed-meshheading:11122337-Imidazoles, pubmed-meshheading:11122337-Long-Term Potentiation, pubmed-meshheading:11122337-NG-Nitroarginine Methyl Ester, pubmed-meshheading:11122337-Neocortex, pubmed-meshheading:11122337-Neuronal Plasticity, pubmed-meshheading:11122337-Nitric Oxide, pubmed-meshheading:11122337-Nitroarginine, pubmed-meshheading:11122337-Rats, pubmed-meshheading:11122337-Rats, Wistar, pubmed-meshheading:11122337-Reaction Time, pubmed-meshheading:11122337-Receptors, AMPA, pubmed-meshheading:11122337-Signal Transduction, pubmed-meshheading:11122337-Synapses, pubmed-meshheading:11122337-Synaptic Transmission, pubmed-meshheading:11122337-Visual Cortex
pubmed:year
2000
pubmed:articleTitle
Retrograde signalling with nitric oxide at neocortical synapses.
pubmed:affiliation
Ruhr-University Bochum, Department of Neurophysiology, MA 4/149, D-44780, Bochum, Germany. maxim@neurop.ruhr-uni-bochum.de
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't