Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1984-5-2
pubmed:abstractText
Both bradykinin (EC50 = 8 ng/ml) and the ionophore A23187 (EC50 = 3 X 10(-7) M) potently stimulated arachidonate release and prostaglandin synthesis in porcine aortic endothelial cells. The response to each was completely dependent on extracellular Ca2+ (EC50 = 3 X 10(-7) M); no role for intracellular Ca2+ was noted. The rapid Ca2+ influx prompted by either activator was consistent with the time course for arachidonate release. Whereas the arachidonate released in response to bradykinin was transient, that released in response to A23187 was more prolonged, and paralleled a continued influx of Ca2+. Ca2+ entry elicited by bradykinin was mediated by channels which could not be blocked by verapamil. When Mn2+ was substituted for Ca2+, no stimulation of prostacyclin synthesis was seen in response to A23187; however, the bradykinin response was unaffected. The mechanism of these effects was studied using doses of bradykinin or A23187 which resulted in increases in Ca2+ influx and prostacyclin synthesis of similar magnitude for each agonist. Under these conditions, trifluoperazine blocked elevated prostacyclin synthesis (ID50 = 5-6 X 10(-6) M for each agonist). Trifluoperazine sulfoxide, however, was much less active. Pimozide inhibited bradykinin-stimulated prostacyclin synthesis at low doses (ID50 = 3 X 10(-6) M). Trifluoperazine was much less effective against high doses of A23187 (4 X 10(-6) M). These data suggest that arachidonate release and prostacyclin synthesis are dependent on influx of extracellular calcium and subsequent activation of a Ca2+-dependent phospholipase by a calmodulin-mediated mechanism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0024-4201
pubmed:author
pubmed:issnType
Print
pubmed:volume
19
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17-24
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
The role of calcium in the regulation of prostacyclin synthesis by porcine aortic endothelial cells.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't