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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
13
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pubmed:dateCreated |
1992-8-4
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pubmed:abstractText |
In the search for more selective A2-receptor agonists and on the basis that appropriate substitution at C2 is known to impart selectivity for A2 receptors, 2-alkynyladenosines 2a-d were resynthesized and evaluated in radioligand binding, adenylate cyclase, and platelet aggregation studies. Binding of [3H]NECA to A2 receptors of rat striatal membranes was inhibited by compounds 2a-d with Ki values ranging from 2.8 to 16.4 nM. 2-Alkynyladenosines also exhibited high-affinity binding at solubilized A2 receptors from human platelet membranes. Competition of 2-alkynyladenosines 2a-d for the antagonist radioligand [3H]DPCPX and for the agonist [3H]CCPA gave Ki values in the nanomolar range, and the compounds showed moderate A2 selectivity. In order to improve this selectivity, the corresponding 2-alkynyl derivatives of adenosine-5'-N-ethyluronamide 8a-d were synthesized and tested. As expected, the 5'-N-ethyluronamide derivatives retained the A2 affinity whereas the A1 affinity was attenuated, resulting in an up to 10-fold increase in A2 selectivity. A similar pattern was observed in adenylate cyclase assays and in platelet aggregation studies. A 30- to 45-fold selectivity for platelet A2 receptors compared to A1 receptors was found for compounds 8a-c in adenylate cyclase studies.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Jun
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pubmed:issn |
0022-2623
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
26
|
pubmed:volume |
35
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
|
pubmed:pagination |
2363-8
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:1619615-Adenosine,
pubmed-meshheading:1619615-Adenosine-5'-(N-ethylcarboxamide),
pubmed-meshheading:1619615-Adenylate Cyclase,
pubmed-meshheading:1619615-Animals,
pubmed-meshheading:1619615-Binding, Competitive,
pubmed-meshheading:1619615-Blood Platelets,
pubmed-meshheading:1619615-Brain Chemistry,
pubmed-meshheading:1619615-Cell Membrane,
pubmed-meshheading:1619615-Cells, Cultured,
pubmed-meshheading:1619615-Humans,
pubmed-meshheading:1619615-Platelet Aggregation,
pubmed-meshheading:1619615-Radioligand Assay,
pubmed-meshheading:1619615-Rats,
pubmed-meshheading:1619615-Receptors, Purinergic
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pubmed:year |
1992
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pubmed:articleTitle |
2-Alkynyl derivatives of adenosine and adenosine-5'-N-ethyluronamide as selective agonists at A2 adenosine receptors.
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pubmed:affiliation |
Dipartimento di Scienze Chimiche, Università di Camerino, Italy.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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