Linked Life Data

8891587

Source:http://linkedlifedata.com/resource/pubmed/id/8891587

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1997-2-6
pubmed:abstractText
In a mast cell model, oxatomide displays inhibition of mediator release which is not related to its histamine H1 receptor antagonistic activity. From a previous study it appeared that especially early steps in the signal transduction leading to exocytosis were influenced by oxatomide. We now studied effects of oxatomide on those early steps in more detail. The antigen- and thapsigargin-mediated exocytosis in rat basophilic leukemia (RBL-2H3) cells were both inhibited by oxatomide. After aggregation of high affinity receptors for immunoglobulin E (Fc epsilon RI), protein tyrosine phosphorylation is induced. Oxatomide caused remarkable changes in the tyrosine phosphorylation pattern in resting cells. Also after antigen and thapsigargin activation, changes in the tyrosine phosphorylation of cellular proteins are observed. In addition, Ca2+ fluxes were studied by means of the net influx of 45Ca2+ and by measuring intracellular free Ca2+ concentrations ([Ca2+]) with the fluorescent probe fura-2. Oxatomide inhibited the 45Ca2+ influx and the increase in [Ca2+]i upon antigen and thapsigargin activation of the cells. Neither the release of Ca2+ from internal stores nor the efflux of Ca2+ over the plasma membrane seems to be affected. The effect of oxatomide on Ca2+ influx was further characterized by studying Ba2+ influx in the absence of extracellular free Ca2+. We conclude that inhibition of mediator release is mainly caused by inhibition of influx of extracellular Ca2+, via plasma membrane Ca2+ channels that are activated by depletion of intracellular Ca2+ stores. The molecular mechanism with which oxatomide might interfere with these channels is discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-2999
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
312
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
121-30
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Influence of the anti-allergic drug oxatomide on the signal transduction mechanism in a mast cell model.
pubmed:affiliation
Department of Pharmaceutical Chemistry, Utrecht Institute for Pharmaceutical Sciences, Faculty of Pharmacy, Utrecht University, Netherlands.
pubmed:publicationType
Journal Article