Metabolism of Cortisol-21 Glucosiduronate in Man*

Abstract
The metabolism of cortisol-21-glucosiduronate has been studied in two subjects. Urinary excretion was about 65% in both subjects, with cortisol glucosiduronate as the principal metabolite accompanied by small amounts of 11β, 17,21-trihydroxypregnane- 3,20-dione (THF) glucosiduronate. The absence of the other normal metabolites of cortisol [17,21-dihydroxypregnane- 3,ll-20-trione (THE), 3α, 11β, 17, 20£, 21-pentahydroxypregnane, and 3α, 17, 20ξ, 21-tetrahydroxypregnan-11-one] indicates that negligible hydrolysis at C-21 occurred and that an unoccupied C21 position is required for oxidation at C-11 and reduction at C-20. The limited conversion to THF suggests that a pathway through cortisol-21-glucosiduronate does not contribute significantly to the differences in specific activity of urinary THF and THE observed after administration of labeled cortisol.