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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1995-3-14
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pubmed:abstractText |
One of the pathways of metabolism of leukotriene B4 (LTB4) and 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) in leukocytes is oxidation of the 12-hydroxyl group, followed by reduction of the 10,11-double bond. In the case of 12R-HETE and 12S-HETE, this results in the formation of 12-oxo-ETE, 10,11-dihydro-12-oxo-ETE, and the 12R and 12S isomers of 10,11-dihydro-12-HETE (i.e., 12R-HETrE and 12S-HETrE). We investigated the effects of metabolites of 12-HETE formed by this pathway on cytosolic calcium levels and chemotaxis in human neutrophils. Of the above series of metabolites, 12S-HETrE (which has the same absolute stereochemistry at C-12 as 12R-HETE) was the most potent in stimulating both cytosolic calcium levels and chemotaxis. It was slightly less potent than 12R-HETE, consistent with the concept that reduction of the 10,11-double bond results in a loss of biological activity on neutrophils. The effect of 12S-HETrE on calcium levels was blocked by preincubation of these cells with LTB4, suggesting that it acted by stimulating the LTB4 receptor. 12R-HETrE was about 20 times less potent than its 12S isomer in stimulating cytosolic calcium in neutrophils and was also less active as a chemotactic agent. Oxidation of the 12-hydroxyl group to an oxo group resulted in a further loss of biological activity. 12-Oxo-ETE, 8-trans-12-oxo-ETE, and 12-oxo-ETrE had only modest effects on cytosolic calcium levels at concentrations as high as 10 microM and did not display detectable chemotactic activity. However, 12-oxo-ETE and its 8-trans isomer inhibited calcium responses to LTB4 by about 40%. It is concluded that reduction of the 10,11-double bond of 12-HETE results in a slight loss of biological activity on neutrophils, whereas oxidation of the 12-hydroxyl group results in a considerably greater loss of activity.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Feb
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pubmed:issn |
0741-5400
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
57
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
257-63
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:7852839-12-Hydroxy-5,8,10,14-eicosatetraenoic Acid,
pubmed-meshheading:7852839-Calcium,
pubmed-meshheading:7852839-Chemotaxis, Leukocyte,
pubmed-meshheading:7852839-Cytosol,
pubmed-meshheading:7852839-Humans,
pubmed-meshheading:7852839-Hydroxyeicosatetraenoic Acids,
pubmed-meshheading:7852839-Intracellular Fluid,
pubmed-meshheading:7852839-Neutrophils,
pubmed-meshheading:7852839-Stereoisomerism
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pubmed:year |
1995
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pubmed:articleTitle |
Effects of oxo and dihydro metabolites of 12-hydroxy-5,8,10,14-eicosatetraenoic acid on chemotaxis and cytosolic calcium levels in human neutrophils.
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pubmed:affiliation |
Meakins-Christie Laboratory, Department of Medicine, McGill University, Montreal, Quebec, Canada.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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