Linked Life Data

1315576

Source:http://linkedlifedata.com/resource/pubmed/id/1315576

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1992-6-10
pubmed:abstractText
Several reports have suggested that the activity of platelet phospholipase A2 is modulated by GTP-binding protein(s) whose nature and properties need to be defined. Fluoroaluminate is known to activate G-proteins and this leads to a number of cellular responses including the activation of phospholipases. This paper demonstrates that human platelets, prelabelled with [3H]arachidonic acid, produce free arachidonic acid when stimulated with fluoroaluminate and this effect is time- and dose-dependent. The production of arachidonic acid is not inhibited by neomycin, a PI-cycle inhibitor, but is completely abolished by mepacrine, an inhibitor of both phospholipase A2 and C. At low concentration of fluoroaluminate (10 mM NaF) phospholipase A2 but not phospholipase C is activated. In addition, fluoroaluminate treatment releases beta-thromboglobulin (beta-TG) and this effect is not inhibited by acetylsalicylic acid. Under identical conditions both neomycin and mepacrine suppress the release of arachidonic acid and beta-TG induced by thrombin. Sodium nitroprusside, which increases cGMP levels in platelets, inhibits arachidonic acid liberation and beta-TG release in thrombin-stimulated platelets but has no effect in fluoroaluminate-treated platelets; cGMP was reported to suppress phospholipase C activation. These results are consistent with the hypothesis that, in thrombin-stimulated platelets, the liberation of arachidonic acid and beta-TG are strictly dependent on the activation of phospholipase C. We have also provided evidence for the existence of a phospholipase A2 activated by a G-protein which is independent from the degradation of phosphoinositides and, contrary to phospholipase C, it is not down regulated by cGMP.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Aluminum, http://linkedlifedata.com/resource/pubmed/chemical/Arachidonic Acid, http://linkedlifedata.com/resource/pubmed/chemical/Cyclic GMP, http://linkedlifedata.com/resource/pubmed/chemical/Fluorine, http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Neomycin, http://linkedlifedata.com/resource/pubmed/chemical/Nitroprusside, http://linkedlifedata.com/resource/pubmed/chemical/Phospholipases A, http://linkedlifedata.com/resource/pubmed/chemical/Phospholipases A2, http://linkedlifedata.com/resource/pubmed/chemical/Quinacrine, http://linkedlifedata.com/resource/pubmed/chemical/Thrombin, http://linkedlifedata.com/resource/pubmed/chemical/Type C Phospholipases, http://linkedlifedata.com/resource/pubmed/chemical/beta-Thromboglobulin, http://linkedlifedata.com/resource/pubmed/chemical/fluoroaluminum
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
1124
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
279-87
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Activation of phospholipase A2 and beta-thromboglobulin release in human platelets: comparative effects of thrombin and fluoroaluminate stimulation.
pubmed:affiliation
Istituto di Biochimica e Chimica Medica, Università di Perugia, Italy.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't