Immunological characterization of urinary 8-epi-prostaglandin F2 alpha excretion in man.
F2-isoprostanes are prostaglandin (PG) F2-like compounds that are formed in vivo directly by free radical-catalyzed lipid peroxidation. One of the compounds that can be produced in abundance by such mechanism is 8-epi-PGF2 alpha, a potent vasoconstrictor. We have developed an enzyme immunoassay and a radioimmunoassay for measuring urinary concentrations of 8-epi-PGF2 alpha by raising antibodies against this compound. The antisera presented high titers (> 1/300,000) and provided highly sensitive assays (IC50, 8 and 24 pg/ml, for EIA and RIA, respectively); cross-reactivity with other PG was negligible. The interassay reproducibility of EIA was assessed by measuring the same urine stored frozen in aliquots after solid phase extraction and thin-layer chromatography (17%, n = 13). Measurements of urinary 8-epi-PGF2 alpha by immunoassays were validated using different antisera and by comparison with gas chromatography/mass spectrometry. Healthy volunteers excreted 25 +/- 12 ng of 8-epi-PGF2 alpha/mmol creatinine (n = 19), with no circadian variation over three consecutive 8-hr collection periods (n = 10); preliminary results showed that excretion increased as a function of age. Urinary excretion of 8-epi-PGF2 alpha was unchanged by treatment with two nonsteroidal antiinflammatory drugs, Ibuprofen at 1.2 g/day for 4 days (n = 4) or aspirin as a single administration of 1 g (n = 6). In contrast, the urinary excretion of 11-dehydro-thromboxane B2, a platelet cyclooxygenase-derived metabolite was reduced by more than 80% after aspirin administration.(ABSTRACT TRUNCATED AT 250 WORDS)
Wang
Z
Z
U348 INSERM, I.F.R. Vaisseaux-Lariboisière Hôpital Lariboisière, Paris, France.
Ciabattoni
G
G
Créminon
C
C
Lawson
J
J
Fitzgerald
G A
GA
Patrono
C
C
Maclouf
J
J
D000328:Adult; D000906:Antibodies; D003429:Cross Reactions; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000097:blood / Q000276:immunology / Q000652:urine; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D012016:Reference Values; D015203:Reproducibility of Results; D014662:Vasoconstrictor Agents / Q000097:blood / Q000276:immunology / Q000652:urine*
D000906:Antibodies; D014662:Vasoconstrictor Agents; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost