PLASMA DEHYDROEPIANDROSTERONE SULFATE SERVES AS A PREHORMONE FOR 48-PERCENT OF FOLLICULAR-FLUID TESTOSTERONE DURING TREATMENT WITH MENOTROPINS

Evidence has suggested that dehydroepiandrosterone sulfate (DS) is a p rehormone for ovarian steroidogenesis. To study this hypothesis, combi ned 6-h infusions of [H-3]dehydroepiandrosterone sulfate and [C-14]tes tosterone ([C-14]T) were performed in four normal women treated with m enotropins who were undergoing medically indicated surgery, and the da ta were compared to those from nine normal women. The concentrations o f tracer and nonisotopic DS, androst-5-ene-3beta,17beta-diol sulfate ( DELTA5diolS), androst-5-ene-3beta,17beta-diol (DELTA5diol), dehydroepi androsterone (D), androstenedione (DELTA4A), and T were determined in arterial and venous blood and in follicular fluid. From these data, th e concentrations and fractions of steroids in the follicular fluid tha t were derived from DS were calculated from the specific activity of i ntravascular DS and the concentrations of follicular fluid tracer ster oids and their specific activities. The fractions of T (0.48), DELTA5d iol (0.31), DELTA5diolS (0.42), and D (0.25) in follicular fluid arisi ng from circulating DS were similar and were not significantly differe nt from that of follicular DS arising from circulating DS (0.32). Howe ver, the fraction of follicular fluid DELTA4A (0.041) was significantl y less (P < 0.01), and the fractions of intrafollicular estrone and es tradiol arising from DS were both less than 0.04. The mean MCR of DS i n the women treated with menotropins of 22.0 +/- 3.5 L/day (mean +/- S E) was significantly higher than the normal control value. These findi ngs elucidate an important mechanism of adrenal/ovarian interaction at the level of steroidogenesis; circulating DS serves as a prehormone f or the production of intrafollicular DELTA5diolS, DELTA5diol, D, and T .