Linked Life Data

10611440

Source:http://linkedlifedata.com/resource/pubmed/id/10611440

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
2000-2-3
pubmed:abstractText
The activation of eosinophils with the lipid mediator, leukotriene B(4), induces their homotypic aggregation. Upon activation with leukotriene B(4), eosinophils release a significant amount of arachidonic acid, a process dependent on the activation of phospholipase A(2). Here, we have evaluated whether arachidonic acid could induce aggregation of eosinophils and whether the release of arachidonic acid mediated the aggregation induced by leukotriene B(4). The exogenous administration of arachidonic acid induced a concentration-dependent eosinophil homotypic aggregation. Pretreatment of eosinophils with a 5-lipoxygenase inhibitor or a leukotriene B(4) receptor antagonist abrogated arachidonic-acid-induced aggregation. Arachidonic acid induced a significant increase in leukotriene B(4) levels and desensitised leukotriene B(4)-induced aggregation in a dose-dependent manner. Moreover, this desensitisation was effectively reversed by a 5-lipoxygenase inhibitor. However, arachidonic acid failed to induce a rise in intracellular Ca(2+) in eosinophils and failed to desensitise these cells to rises in intracellular Ca(2+) induced by leukotriene B(4). Pretreatment of eosinophils with the phospholipase A(2) inhibitor, mepacrine, inhibited the aggregation responses induced by 1 nM leukotriene B(4) by approximately 50% but had no significant effect on the other concentrations of leukotriene B(4) tested (0.1 to 100 nM). In conclusion, arachidonic acid stimulates eosinophil aggregation indirectly via the release of leukotriene B(4). Although a significant amount of arachidonic acid is released in response to activation of eosinophils with leukotriene B(4), the arachidonic acid released does appear to play a major role in mediating leukotriene B(4)-induced eosinophil aggregation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Arachidonic Acid, http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/LY 255283, http://linkedlifedata.com/resource/pubmed/chemical/Leukotriene Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Leukotriene B4, http://linkedlifedata.com/resource/pubmed/chemical/Lipoxygenase Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Phospholipases A, http://linkedlifedata.com/resource/pubmed/chemical/Pyrans, http://linkedlifedata.com/resource/pubmed/chemical/Quinacrine, http://linkedlifedata.com/resource/pubmed/chemical/Quinolones, http://linkedlifedata.com/resource/pubmed/chemical/Tetradecanoylphorbol Acetate, http://linkedlifedata.com/resource/pubmed/chemical/Tetrazoles, http://linkedlifedata.com/resource/pubmed/chemical/ZM 230487
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0014-2999
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
384
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
183-90
pubmed:dateRevised
2009-9-29
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Role of arachidonic acid in leukotriene B(4)-induced guinea-pig eosinophil homotypic aggregation.
pubmed:affiliation
Laboratório de Imunofarmacologia, Departamento de Farmacologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627 Pampulha, Belo Horizonte, Brazil. mmtex@icb.ufmg.br
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't