Linked Life Data

9103452

Source:http://linkedlifedata.com/resource/pubmed/id/9103452

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1997-5-5
pubmed:abstractText
Activation of rat peritoneal macrophages by LPS resulted in time-dependent production of nitric oxide and enhancement of cyclooxygenase (Cox) activity. This stimulation was accompanied by increased expression of inducible enzymes, NO synthase, and Cox-2, contrasting with no variation in constitutive Cox-1. Inhibition of NO production in LPS-treated macrophages by either the L-arginine analogue N(G)-monomethyl-L-arginine (L-NMMA) or aminoguanidine was accompanied by an additional enhancement of Cox activity parallel to the expression of Cox-2 protein analyzed by Western blot. Addition of NO donors (3-morpholinosydnonimine (Sin-1), sodium nitroprusside, or S-nitrosoglutathione) reversed the effects of L-NMMA, confirming the role of NO on Cox-2 expression. Specific immunoprecipitation of Cox-2 showed a pattern of protein expression similar to that observed in intact cells. Enzyme activity tested on the immunoprecipitates was correlated with the enzyme mass. In contrast, there was no variation in immunoprecipitated Cox-1 protein or in activity. Levels of mRNA for Cox-2 were increased in macrophages stimulated by LPS in the presence of L-NMMA compared with LPS alone. Metabolic labeling using [35S]methionine showed that inhibition of NO formation resulted in enhanced de novo synthesis of the 35S-labeled Cox-2. The amount of Cox-2 protein induced in the presence or absence of L-NMMA did not change for at least 6 h, suggesting that NO does not modify the t1/2 of the enzyme. These results provide evidence that NO participates in PG production by negative regulation of Cox-2 expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
158
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3845-51
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Regulation of the expression of cyclooxygenase-2 by nitric oxide in rat peritoneal macrophages.
pubmed:affiliation
Unit U348, Lariboisiere Hospital, Federated Institute of Research (IFR) Biology of Circulation-Lariboisiere, Paris, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't