Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1983-5-5
pubmed:abstractText
The characteristics of the binding of the dopamine receptor antagonist [3H]spiroperidol to rat striatal membranes were examined at six different incubation temperatures ranging from 1 degree to 37 degrees. Although the number of receptors labeled at each temperature was identical, the affinity of the receptor for [3H]spiroperidol decreased 10-fold as the incubation temperature was lowered from 37 degrees to 1 degree. The binding of [3H]spiroperidol was entropy-driven (delta S degree = +80 cal/mole-deg), endothermic (delta H degree = +10 kcal/mole), and exergonic (delta G degree = -13 kcal/mole). Qualitatively similar results were found for (+)-butaclamol, another dopamine receptor antagonist. The binding of the agonists dopamine and (+/-)-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene to sites labeled by [3H]spiroperidol in the striatum also appeared to be entropy-driven (delta S degree = +35 cal/mole-deg). In contrast to the results obtained in studies with antagonists, however, the affinity of the receptor for agonists was independent of the incubation temperature between 8 degrees and 37 degrees. Competition curves for the inhibition of [3H]spiroperidol binding by agonists became increasingly complex as the incubation temperature was lowered. The addition of GTP reduced the affinity of the receptor for agonists at all temperatures but did not simplify interpretation of these complex curves. At 1 degree there was a decrease in the affinity of the receptor for dopamine, and the effect of GTP was abolished.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
303-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Thermodynamic differences between agonist and antagonist interactions with binding sites for [3H]spiroperidol in rat striatum.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.