Conversion of DHEA into downstream steroid hormones in mixed synovial cells. (a,b) Spontaneous conversion of radiolabeled DHEA into downstream metabolites in OA (open bars, n = 24) and RA patients (hatched bars, n = 23). The E3 and 16αOH-testosterone produced are shown together in one bar because only one spot was detected for both steroids using TLC. The bar '16αOH all' reflects the sum of all 16α-hydroxylated products. (c,d) Conversion of radiolabeled DHEA into testosterone under the influence of 5α-dihydrotestosterone as investigated in three OA and one RA patient. All panels: values are given as pmol/106 cells/48 hr as box blots with the 5th, 25th, 50th (median), 75th, and 95th percentile when applicable. * Denotes radiolabeled substrate. OA, osteoarthritis; RA, rheumatoid arthritis. Other abbreviations are as given in the legend to Fig. 1.