Fig. (4) Effects of various drugs on oxidative Epo B metabolism
by human liver microsomes. A pool of human liver microsomes
(0.75 nmoles P450) was incubated with 120 µM Epo B in presence
of 10µM troleandomycin (TAO), 400µM erythromycin (Eryt),
25µM ciclosporin A (Ci A), 150µM verapamil, 5µM docetaxel,
30µM paclitaxel, 15M vinblastine, 15µM vincristine, 100µM
etoposide (VP16) or 60µM irinotecan. After 60 min the reaction
was stopped, Epo B and its metabolite were extracted with dichloromethane
and separated by HPLC. Results are calculated as
the residual activity and expressed as a percentage of the activity
measured in absence of drugs (control).