Metabolism of Thromboxane B, in the Monkey*

[3H8]Thromboxane Bz was biosynthesized and infused into an unanesthetized monkey. Several urinary metabolites were isolated and their structures elucidated using gas chromatography-mass spectrometry. In addition to the major urinary metabolite, dinor-thromboxane Bz, a series of metabolites resulting from dehydrogenation of the alcohol group at C-11 were identified: 11-dehydro-thromboxane Bz, 11-dehydro-15-keto-13, 14-dihydro-2,3-dinor-thromboxane Bz, and ll-dehydro-15-keto-13,14-dihydro-19-carboxyl-2,3,4,5-tetranor-thromboxane Bz. 6-(1,3-dihydroxypropyl)-7-hydroxy-lo-oxo-3-pentadecaenoic acid was also identified. Three mono-0-ethylated metabolites were formed from thromboxane Bz, which in this study was infused in an ethanolic solution. A small quantity of thromboxane Bz was excreted unchanged into the urine.