Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
2005-12-5
pubmed:abstractText
Few studies have addressed the effects of classical anti-inflammatory glucocorticoids on platelet function. Here, we report for the first time that human platelets contain the glucocorticoid receptor (GR) as identified by a combination of biochemical and functional techniques. Ligand-binding studies revealed the presence of a high- and low-affinity binding site for [3H]-dexamethasone in platelets. The 2 GR ligands prednisolone and dexamethasone competed for [3H]-dexamethasone binding, as did the mineralocorticoid aldosterone. However, while prednisolone (1-10 microM) reduced adenosine diphosphate (ADP, 4 microM) and thromboxane A2 receptor agonist U46619 induced platelet aggregation (up to 75%), dexamethasone had no effect. The inhibition produced by prednisolone was reversed by preincubation with the GR antagonist mifepristone (10 microM; RU486), suggesting the functional importance of the ligand-receptor complex. In addition, prednisolone caused a marked (approximately 50%) reduction in thromboxane B2 levels, whereas dexamethasone was without effect. The apparently anomalous binding data were clarified by the fact that washed platelets (1) contained mineralocorticoid receptor and that (2) it was associated with GR. Taken together, our data suggest that platelet GR forms a heterodimeric complex with the mineralocorticoid receptor that is susceptible to differential activation by specific receptor ligands.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
106
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4167-75
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Ligand-specific glucocorticoid receptor activation in human platelets.
pubmed:affiliation
The William Harvey Research Institute, Charterhouse Square, London EC1M 6BQ, United Kingdom.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't