Linked Life Data

9482785

Source:http://linkedlifedata.com/resource/pubmed/id/9482785

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-4-13
pubmed:abstractText
ATP analogs substituted in the gamma-phosphorus (ATPgammaS, beta, gamma-imido-ATP, and beta,gamma-methylene-ATP) were used to probe the involvement of P2 receptors in the modulation of synaptic transmission in the hippocampus, because their extracellular catabolism was virtually not detected in CA1 slices. ATP and gamma-substituted analogs were equipotent to inhibit synaptic transmission in CA1 pyramid synapses (IC50 of 17-22 microM). The inhibitory effect of ATP and gamma-phosphorus-substituted ATP analogs (30 microM) was not modified by the P2 receptor antagonist suramin (100 microM), was inhibited by 42-49% by the ecto-5'-nucleotidase inhibitor and alpha,beta-methylene ADP (100 microM), was inhibited by 74-85% by 2 U/ml adenosine deaminase (which converts adenosine into its inactive metabolite-inosine), and was nearly prevented by the adenosine A1 receptor antagonist 1,3-dipropyl-8-cyclopentylxanthine (10 nM). Stronger support for the involvement of extracellular adenosine formation as a main requirement for the inhibitory effect of ATP and gamma-substituted ATP analogs was the observation that an inhibitor of adenosine uptake, dipyridamole (20 microM), potentiated by 92-124% the inhibitory effect of ATP and gamma-substituted ATP analogs (10 microM), a potentiation similar to that obtained for 10 microM adenosine (113%). Thus, the present results indicate that inhibition by extracellular ATP of hippocampal synaptic transmission requires localized extracellular catabolism by ecto-nucleotidases and channeling of the generated adenosine to adenosine A1 receptors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0270-6474
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1987-95
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Inhibition by ATP of hippocampal synaptic transmission requires localized extracellular catabolism by ecto-nucleotidases into adenosine and channeling to adenosine A1 receptors.
pubmed:affiliation
Department of Chemistry and Biochemistry, Faculty of Sciences, University of Lisbon, 1600 Lisbon, Portugal.
pubmed:publicationType
Journal Article, In Vitro, Review, Research Support, Non-U.S. Gov't