“…The experiment of inhibition percentage of Apa was measured by the generating rate of metabolite in the presence of 100 μM Apa (study group) compared with no inhibitor (control group). In the experiment of IC 50 determination, the concentration of Apa was set as 0.01, 0.1, 1, 10, 50 and 100 μM, while that of Ven was 100 μM, which is close to its K m value . In the experiment of determining the inhibitory effect of Apa on Ven in RLM and HLM, the concentration of Apa was designed at 0, 2, 5 and 10 μM according to the IC 50 value, while the concentration of Ven was designed at 25, 50, 100, 200 μM according to the K m value.…”