the activity of 3 beta-hydroxysteroid dehydrogenase/isomerase ( 3 beta-hsd ) , 17-hydroxylase ( 17-ohase ) , 17,20-desmolase ( 17,20d ) , 17-ketosteroid reductase ( 17-ksr ) and aromatase were measured using a constant amount ( 50 microm ) of 14c-labelled substrates in the presence of varying concentrations of pure ketoconazole .
C0030016
dehydrogenase
C0003805
aromatase