title: Determination of free and glucuronide conjugated 20-hydroxyarachidonic acid (20-HETE) in urine by gas chromatography/negative ion chemical ionization mass spectrometry.
abstract: 20-Hydroxy-arachidonic acid (20-HETE) was determined in urine by an isotope dilution assay using gas chromatography/mass spectrometry (GC/MS). After addition of 18O2-internal standard, 20-HETE was extracted from urine with hexane either directly or after treatment with glucuronidase. 20-HETE was derivatized to the pentafluorobenzylester and the sample was applied to thin layer chromatography with iso-octane/iso-propanol 9:1 (v/v) as the developing solvent. The corresponding zone was extracted and 20-HETE was hydrogenated. After derivatization to the trimethylsilylether, 20-HETE was determined by GC/MS using the [M-pentafluorobenzyl]- -ion in the negative ion chemical ionization mode. Excretion rates of free and glucuronide conjugated 20-HETE was determined in healthy children and in children with hyperprostaglandin-E-syndrome/antenatal Bartter syndrome (HPS/aBS) with or without indomethacin treatment. Compared to the controls, the HPS/aBS children showed higher excretion rates of 20-HETE, which were suppressed to normal values under indomethacin medication. Free and glucuronide conjugated 20-HETE do not correlate with PGE2 excluding any participation in HPS/aBS.
authors.affiliation: Department of Pediatrics, Philipps University Marburg, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Watzer
authors.forename: S
authors.initials: S
authors.lastname: Reinalter
authors.forename: H W
authors.initials: HW
authors.lastname: Seyberth
authors.forename: H
authors.initials: H
authors.lastname: Schweer
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015232:Dinoprostone / Q000037:antagonists & inhibitors / Q000652:urine; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D020719:Glucuronides / Q000652:urine*; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000652:urine*; D007177:Inappropriate ADH Syndrome / Q000188:drug therapy / Q000652:urine; D007213:Indomethacin / Q000627:therapeutic use; D008297:Male; D010103:Oxygen Isotopes / Q000032:analysis
chemical_list: D020719:Glucuronides; D006893:Hydroxyeicosatetraenoic Acids; D010103:Oxygen Isotopes; C055987:20-hydroxy-5,8,11,14-eicosatetraenoic acid; D015232:Dinoprostone; D007213:Indomethacin