Linked Life Data

2982516

Source:http://linkedlifedata.com/resource/pubmed/id/2982516

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1985-3-22
pubmed:abstractText
The density of adenosine receptors in membranes derived from rat hearts in 25 times lower than the density of receptors in rat brain membranes. Consequently, adenosine radioligands which are useful in brain such as l-[3H]phenylisopropyladenosine, [3H]cyclohexyladenosine, [3H]-2-chloroadenosine and l-[125I]hydroxyphenylisopropyladenosine are of limited usefulness in heart, due to a high ratio of nonspecific to specific binding. We have synthesized a new radioligand, [125I]-N6-4-aminobenzyladenosine, which binds to rat heart membranes with one-sixth the nonspecific binding of the other radioligands. [125I]-N6-4-aminobenzyladenosine bound to rat ventricle membranes with a KD equivalent to that of l-[125I]hydroxyphenylisopropyladenosine and a Bmax of 15.2 fmol/mg protein. [125I]-N6-4-aminobenzyladenosine bound with a higher affinity to brain (KD = 1.93 nM) than to heart membranes (KD = 11.6 nM). At the radioligand KD, 60% of the total [125I]-N6-4-aminobenzyladenosine bound to heart membranes was specifically bound. Iodination of aminobenzyladenosine increased its affinity for the adenosine receptor by 22-fold, possibly due to a steric or hydrophobic effect of iodine. The new ligand was found to be a full adenosine agonist based on its ability to inhibit cyclic adenosinemonophosphate accumulation in isolated embryonic chick heart cells and rat adipocytes. [125I]-N6-4-Aminobenzyladenosine bound to a single affinity site and was displaced from cardiac and brain adenosine receptors by other adenosine analogues with a potency order of l-phenylisopropyladenosine greater than 5'-N-ethylcarboxamide adenosine. These characteristics suggest that the radioligand binds to an Ri adenosine receptor.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0009-7330
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
279-84
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
[125I]Aminobenzyladenosine, a new radioligand with improved specific binding to adenosine receptors in heart.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't