Linked Life Data

10583475

Source:http://linkedlifedata.com/resource/pubmed/id/10583475

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1999-12-28
pubmed:abstractText
Depotentiation comprises a reversal of tetanization-induced long-term potentiation (LTP) which occurs following low-frequency stimulation (LFS) in the hippocampus in vivo. Although depotentiation has been consistently demonstrated in the CA1 region, no positive reports of the existence of depotentiation in the dentate gyrus in vivo have occurred. This study therefore investigated whether depotentiation is possible in the dentate gyrus in vivo. We found that depotentiation can be induced, but it is very tightly dependent on the interval between tetanization and LFS. Thus, LFS given 2 or 5 min following tetanization produced significant depotentiation, whereas LFS given 10-30 min following tetanization had no significant effect on the expression of LTP. Depotentiation occurred in two phases: a transient depression of evoked responses to below pre-tetanization values, which occurred in the first 60 min following LFS, and a recovery of this response to a stable level of synaptic transmission which comprised a significant reduction in the magnitude of LTP. Group 2 metabotropic glutamate receptors (mGluRs) play an important role in the expression of long-term depression in vivo. We therefore investigated whether group 2 mGluRs contribute to depotentiation. The group 2 antagonist (2S)-alpha-ethylglutamic acid (EGLU) inhibited the early transient depression at a concentration which inhibits LTD in vivo, but did not block the expression of depotentiation. EGLU also inhibited the transient depression induced by 5 Hz given alone. Increasing the concentration of EGLU prevented depotentiation, however. The group 2 agonist (S)-4-carboxy-3-hydroxyphenyl- glycine (4C3HPG) inhibited LTP and enhanced depotentiation. These data suggest a role for group 2 mGluRs in depotentiation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0953-816X
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3864-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Time-dependent induction of depotentiation in the dentate gyrus of freely moving rats: involvement of group 2 metabotropic glutamate receptors.
pubmed:affiliation
Leibniz Institute for Neurobiology, Department of Neurophysiology, Brenneckestrasse 6, P.O. Box 1860, D-39008 Magdeburg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't