Linked Life Data

3261295

Source:http://linkedlifedata.com/resource/pubmed/id/3261295

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
1988-9-20
pubmed:abstractText
Human endothelial cells synthesize large amounts of platelet-activating factor (PAF) after 30-min treatment with recombinant tumor necrosis factor (TNF). Synthesis of PAF peaks at 4-6 h, whereas in endothelial cells treated with interleukin 1 alpha (IL-1) it peaks at 8-12 h. More than twice as much PAF is synthesized in response to optimal concentrations of TNF than in response to IL-1. However, PAF synthesis is stimulated by lower molar concentrations of IL-1 than TNF. About 30% of PAF produced in response to either TNF or IL-1 is released into the medium, whereas approximately 70% remains cell-associated. Experiments with labeled precursors show that PAF is synthesized de novo in response to TNF. This activity of TNF is inhibited by treating endothelial cells with the inhibitors of protein or RNA synthesis cycloheximide or actinomycin D. This finding may be explained by the observation that TNF induces in endothelial cells an acetyltransferase required for PAF synthesis. The induction of this enzymatic activity precedes the peak of PAF synthesis in TNF-treated cells. After prolonged incubation with either TNF or IL-1, endothelial cells no longer respond to the same monokine, but are still capable of producing PAF when treated with the other monokine. The finding that these monokines do not show reciprocal tachyphylaxis in endothelial cells may be explained by their binding to different receptors. In cells treated simultaneously with different concentrations of TNF and IL-1, PAF synthesis is stimulated in an additive rather than synergistic way. This suggests that PAF is synthesized by the same pathway in response to TNF or IL-1.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
263
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11856-61
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Synthesis and release of platelet-activating factor by human vascular endothelial cells treated with tumor necrosis factor or interleukin 1 alpha.
pubmed:affiliation
Cattedra di Chimica e Propedeutica Biochimica, Università di Torino, Italy.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't