CYP catalysis | Inhibitors | Inhibition at Various Concentrations, M | ||||
---|---|---|---|---|---|---|
1 × 10−8 | 1 × 10−7 | 1 × 10−6 | 1 × 10−5 | 1 × 10−4 | ||
CYP2D6 | Quinidine | 35.6 | 77.1 | >92.1 | >92.1 | >92.1 |
CYP3A4 | Troleandomycin | —1-a | 9.5 | 52.3 | 87.9 | >89.3 |
Ketoconazole | 0.6 | 20.2 | 77.5 | >89.3 | —1-a |
Dehydrogenated pranidipine (10 μM) was incubated with 1 mg/ml of microsomal protein in the assay medium. Control activities in the CYP2D6- and 3A4-mediated reactions were 0.29 and 0.35 nmol/min/nmol P-450, respectively. Enzyme incubation and metabolite analysis were carried out in duplicate and the data were expressed as the mean. Differences found between the duplicate values were less than ±18% of the mean values.
↵1-a Not performed.