Linked Life Data

9423285

Source:http://linkedlifedata.com/resource/pubmed/id/9423285

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1998-2-9
pubmed:abstractText
F2-isoprostanes are considered to be novel markers of lipid peroxidation. To study the in vivo formation of F2-isoprostanes, an improved method was developed for isotope dilution assays involving gas chromatography/triple-stage quadrupole mass spectrometry (GC/MS/MS) including thin-layer chromatography (TLC) (sum of all F2-isoprostanes) and high-performance liquid chromatographic (HPLC) purification (prostaglandin F2 alpha (PGF2 alpha) and 8-epi-PGF2 alpha). Following the addition of isotopically labeled prostaglandins to urine, the sample was acidified and applied to a C18 cartridge. After elution, prostaglandins were derivatized to pentafluorobenzyl esters and subjected to TLC. A broad zone was scratched off, isoprostanes were eluted and after formation of their trimethylsilyl ether derivatives the sum of F2-isoprostanes was determined by GC/MS/MS. For the determination of PGE2 alpha and 8-epi-PGF2 alpha prior to trimethylsilylation an additional HPLC step was performed and the fractions containing PGF2 alpha and 8-epi-PGF2 alpha were analyzed by GC/MS/MS. Using this technique, 8-epi-PGF2 alpha concentrations in urine samples as low as 5 pg ml-1 could be determined with high accuracy. The excretion rates of isoprostanes were studied in comparison with the classical prostaglandins in three different groups: healthy adults, healthy children and children with hyper-PGE syndrome (HPS), a pathological situation associated with a stimulated PGE2 synthesis. F2-isoprostanes represented the main arachidonic acid metabolites in these groups and 8-epi-PGF2 alpha excretion was comparable in its amount to the classical prostanoids. To delineate the cyclooxygenase-catalyzed contribution, the influence of indomethacin, an inhibitor of cyclooxygenases, on F2-isoprostane formation in healthy adults and in HPS children was analyzed. Significantly decreased excretion rates were observed 2 days after indomethacin administration for all prostanoids, including F2-isoprostanes and 8-epi-PGF2 alpha. However, the suppression of F2-isoprostanes and 8-epi-PGF2 alpha excretion rates was less pronounced in comparison with the classical prostanoids. An improved and reliable method for the determination of F2-isoprostanes and especially 8-epi-PGF2 alpha has been developed. The data obtained on human urine samples indicates a contribution of the cyclooxygenase pathway to the formation of isoprostanes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1076-5174
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1362-70
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:9423285-Adolescent, pubmed-meshheading:9423285-Adult, pubmed-meshheading:9423285-Child, pubmed-meshheading:9423285-Chromatography, High Pressure Liquid, pubmed-meshheading:9423285-Chromatography, Thin Layer, pubmed-meshheading:9423285-Cyclooxygenase Inhibitors, pubmed-meshheading:9423285-Dinoprost, pubmed-meshheading:9423285-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:9423285-F2-Isoprostanes, pubmed-meshheading:9423285-Female, pubmed-meshheading:9423285-Gas Chromatography-Mass Spectrometry, pubmed-meshheading:9423285-Humans, pubmed-meshheading:9423285-Indicators and Reagents, pubmed-meshheading:9423285-Indomethacin, pubmed-meshheading:9423285-Male, pubmed-meshheading:9423285-Metabolism, Inborn Errors, pubmed-meshheading:9423285-Prostaglandin-Endoperoxide Synthases, pubmed-meshheading:9423285-Reference Values
pubmed:year
1997
pubmed:articleTitle
Improved quantification of 8-epi-prostaglandin F2 alpha and F2-isoprostanes by gas chromatography/triple-stage quadrupole mass spectrometry: partial cyclooxygenase-dependent formation of 8-epi-prostaglandin F2 alpha in humans.
pubmed:affiliation
Children's Hospital, Philipps University Marburg, Germany.
pubmed:publicationType
Journal Article, Clinical Trial