Rapid, direct enzyme immunoassay of 11-keto-thromboxane B2 in urine, validated by immunoaffinity/gas chromatography-mass spectrometry.
We have developed a direct enzyme immunoassay (EIA) for quantifying immunoreactive 11-keto-thromboxane B2 (iKTXB) in unprocessed human urine. Cross-reactivity with other thromboxane metabolites and prostanoids was negligible. Analytical recovery of 11-keto-TXB2 in urine specimens was 97.4% to 99.8%. Total imprecision for two clinical specimens was 8.5% and 12.2%. Intake of acetylsalicylic acid decreased the measured concentration of iKTXB. Cardiopulmonary bypass, a procedure known to activate platelets, increased the mean excretion rate of iKTXB 10-fold. Simultaneous gas chromatography-mass spectrometry analysis of 11-keto-TXB2 and 11-keto-2,3-dinor TXB2 in urine specimens (n = 17) from healthy subjects indicated that urinary iKTXB concentrations measured by EIA represented a sum of the two 11-keto metabolites. We conclude that the direct EIA is sufficiently sensitive, rapid, simple, and specific to allow screening for alterations in thromboxane biosynthesis in patients.
Djurup
R
R
Novo Nordisk, Immunochemical Department, Bagsvaerd, Denmark.
Chiabrando
C
C
Jörres
A
A
Fanelli
R
R
Foegh
M
M
Soerensen
H U
HU
Joergensen
P N
PN
D001241:Aspirin / Q000652:urine; D002315:Cardiopulmonary Bypass; D005188:False Negative Reactions; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007124:Immunoenzyme Techniques / Q000706:statistics & numerical data; D015539:Platelet Activation; D011786:Quality Control; D012680:Sensitivity and Specificity; D013929:Thromboxane B2 / Q000031:analogs & derivatives* / Q000652:urine
D013929:Thromboxane B2; C028965:2,3-dinor-thromboxane B2; C049235:11-dehydro-thromboxane B2; D001241:Aspirin