Linked Life Data

2543147

Source:http://linkedlifedata.com/resource/pubmed/id/2543147

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-7-3
pubmed:abstractText
1. The cytochrome P-450-dependent metabolism of leukotriene B4 (LTB4) by rat hepatic microsomes was characterized. Hepatic microsomes were found to metabolize LTB4 to 20-hydroxy-LTB4 and 20-carboxy:LTB4. The rate of formation of 20-hydroxy-LTB4 (14.6 pmol/min per mg protein) was 5.8-fold higher than that of 20-carboxy-LTB4 (2.5 pmol/min per mg protein). 2. LTB4 omega-hydroxylase activity required NADPH and oxygen indicating that the reaction is mediated by a mono-oxygenase system. The omega-hydroxylase activity was optimal at pH 7.4 and product formation was linear with respect to time of incubation and protein concentration. The reaction was significantly inhibited by carbon monoxide (89%), SKF 525-A (1 mM), and metyrapone (0.1 mM) whereas alpha-naphthoflavone had only marginal inhibitory effects. The apparent Km and Vmax of LTB4 omega-hydroxylase were 4 microM and 19.6 pmol/min per mg protein, respectively. 3. Ontogenic studies revealed that LTB4 omega-hydroxylase activity was low in 4-day-old rats and that there was a steady increase in enzyme activity as the animal matured. 4. Phenobarbital, 3-methylcholanthrene or Aroclor 1254 treatment of rats did not induce LTB4 omega-hydroxylase activity whereas clofibrate resulted in 61% induction in enzyme activity. No significant sex-dependent differences were observed. 5. It is concluded that hepatic metabolism of LTB4 may afford an effective mechanism for limiting many of the pro-inflammatory effects of circulating leukotrienes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0049-8254
pubmed:author
pubmed:issnType
Print
pubmed:volume
19
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
151-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Hepatic microsomal metabolism of leukotriene B4 in rats: biochemical characterization, effect of inducers, and age- and sex-dependent differences.
pubmed:affiliation
Department of Dermatology, University Hospital of Cleveland, Case Western Reserve University, Ohio.
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