Metabolic Clearance Rate of Dehydroepiandrosterone Sulfate, Its Metabolism to Testosterone, and Its Intrafollicular Metabolism to Dehydroepiandrosterone, Androstenedione, Testosterone, and Dihydrotestosterone in Vivo*

At the time of surgery, women were infused with [3H]dehydoepiandrosterone sulfate ([3H]DS)/[14C]testosterone ([14C]T) for 6 h; blood samples were obtained from an artery, the ovarian veins, and a peripheral vein; and fluid was obtained from ovarian follicles. Both blood and follicular fluid samples were analyzed for radioactivity as DS, dehydroepiandrosterone (D), androstenedione (Δ4A), T, and dihydrotestosterone (DHT), and the blood was also analyzed for the concentration of nonisotopic DS by RIA. In other subjects the concentrations of D and DS were measured in paired samples of blood and follicular fluid. From these data, values of 13.6 ± 0.69 L/day four (mean ± se; n = 4) for MCRDS, 607 ± 90 L/day (n = 3) for MCRT, and 0.0190 ± 0.0089 (n = 3) for [ρ]DS-T (fraction of plasma DS metabolized to plasma T) were obtained. The ratio of the concentration of the tracer-labeled steroid in the follicular fluid to the concentration in the arterial plasma sample was elevated significantly above 1 for three 3H-labe...