Linked Life Data

9134216

Source:http://linkedlifedata.com/resource/pubmed/id/9134216

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1997-8-27
pubmed:abstractText
1. We have previously shown that both suramin and pyridoxal-phosphate-6-azophenyl-2',4' disulphonic acid (PPADS) act as antagonists at transfected P2Y1 receptors. Here we show that under certain experimental conditions these two P2 antagonists can enhance the response to agonists acting at these receptors. 2. The expression of either P2Y1 or P2Y2 receptors in 1321N1 human astrocytoma cells results, on a change of medium, in an elevation of basal (no added agonist) accumulation of [3H]-inositol(poly)phosphates([3H]-InsPx) compared to cells not expressing these receptors. This elevation is much greater in P2Y1 transfectants than in P2Y, transfectants. 3. Both PPADS and suramin reduced this basal level of [3H]-InsPx accumulation in the P2Y1 expressing cells. 4. When a protocol was used which required changing the culture medium, antagonists were added at a concentration which reduced the basal accumulation by about 50%, there was a significant stimulation in response to increasing concentrations of 2-methylthioadenosine 5'-triphosphate (2MeSATP), in the absence of antagonists there was no significant effect of the agonist. 5. However, when 2MeSATP was added in the absence of a change of medium and with no antagonist present, there was a several fold increase in [3H]-InsPx accumulation. These results show that a release of endogenous agonist activity (possibly ATP/ADP) from the P2Y1 expressing cells can create conditions in which a response to an agonist such as 2MeSATP can only be seen in the presence of a competitive antagonist.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0007-1188
pubmed:author
pubmed:issnType
Print
pubmed:volume
120
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1049-52
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Enhancement of the response to purinergic agonists in P2Y1 transfected 1321N1 cells by antagonists suramin and PPADS.
pubmed:affiliation
Department of Cell Physiology and Pharmacology, University of Leicester.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't