Inhibitor or anti-P450 IgG | Target P450 | M2 | M4 |
---|---|---|---|
% control | |||
Sulfaphenazole 20 μM | 2C9 | 100 | 100 |
Troleandomycin 40 μM | 3A4 | 60 | 21 |
Quinidine 40 μM | 2D6 | 100 | 100 |
Anti-3A4 IgG 5 mg/IgG/nmol of P4501-b | 3A4 | 70 | 16 |
Anti-2D6 IgG 5 mg/IgG/nmol of P4501-b | 2D6 | 100 | 100 |
↵1-a 1 in phosphate buffer was added to human liver microsomes suspended in phosphate buffer (0.1 M, pH 7.4) containing EDTA. The final concentration of the compound was 25 μM. Sulfaphenazole and quinidine were preincubated with microsomes for 10 min, and troleandomycin was preincubated with microsomes in the presence of NADPH for 15 min at 37°C. Reactions were initiated by adding the substrate and another portion of NADPH and proceeded for an additional 10 min. The products were analyzed by LC/MS/MS.
↵1-b Anti-CYP 2D6 IgG or anti-CYP3A4 IgG was preincubated with microsomes for 30 min at room temperature. Control incubations contained preimmune IgG. Reactions were initiated by adding the substrate and another portion of NADPH and proceeded for additional 10 min. The products were analyzed by LC/MS/MS.