Measurement of urinary 8-Epi-prostaglandin F2alpha, a novel index of lipid peroxidation in vivo, by immunoaffinity extraction/gas chromatography-mass spectrometry. Basal levels in smokers and nonsmokers.
8-Epi-prostaglandin F2alpha (8-epi-PGF2alpha) is an F2-isoprostane recently identified as a marker of free radical-catalyzed lipid peroxidation in vivo and potential mediator of oxidative damage. Currently, endogenous 8-epi-PGF2alpha is measured by gas chromatography-mass spectrometry after lengthy sample preparation. We extracted and purified 8-epi-PGF2alpha in one step from biological samples on immunoaffinity columns prepared with an anti-8-epi-PGF2alpha antiserum, raised in our laboratory. Quantitation was done by stable-isotope dilution gas chromatography/negative-ion chemical ionization mass spectrometry, with selected ion recording. Carboxylate anions of the pentafluorobenzyl ester trimethylsilyl ether derivative of 8-epi-PGF2alpha and [2H4]8-epi-PGF2alpha were monitored (m/z 569 and 573). Basal urinary excretion of 8-epi-PGF2alpha can be accurately and rapidly measured by this method. Under normal conditions rats (n = 30) excreted 2.18 +/- 0.68 ng/24 h. In healthy nonsmoking young volunteers, urinary excretion of 8-epi-PGF2alpha, measured three times on alternate days, was fairly constant (CV 2-10%). Nonsmokers excreted significantly less 8-epi-PGF2alpha than age-matched smokers (8.08 +/- 2.3 vs. 18.40 +/- 4.77 ng/h/1.73 m2; n = 6; p < 0.005), as reported by others using different methods.
Bachi
A
A
Istituto di Ricerche Farmacologiche 'Mario Negri', Milano, Italy.
Zuccato
E
E
Baraldi
M
M
Fanelli
R
R
Chiabrando
C
C
D000818:Animals; D016022:Case-Control Studies; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012907:Smoking / Q000652:urine*; D014662:Vasoconstrictor Agents / Q000652:urine*
D014662:Vasoconstrictor Agents; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost