TABLE 1

Substrate and positive inhibitor of each P450 isoform

P450sSubstrate (Concentration)MetaboliteProbe Inhibitor (Concentration)
μMμM
1A2Phenacetin (50 μM)aAcetaminophenα-naphthoflavone (0.1 μM)
2A6Coumarin (1 μM)7-hydroxycoumarinTryptamine (2 μM)
2B6Bupropion (5 μM)2-hydroxybupropionSertraline (1 μM)
2C8Paclitaxel (5 μM)6α-hydroxypaclitaxelQuercetin (0.5 μM)
2C9Diclofenac (4 μM)4′-hydroxydiclofenacSulfaphenazole (0.5 μM)
Tolbutamide (70 μM)a4-hydroxytolbutamideSulfaphenazole (0.5 μM)
2C19Mephenytoin (1 μM)4′-hydroxymephenytoinNootkatone (0.5 μM)
Oxyomeprazole (20μM)a5-hydroxyomeprazoleTiclopidine (1.0 μM)
2E1Chlorzoxazone (20 μM)a6-hydroxychlorzoxazoneClomethiazole (10 μM)
3A4/5Midazolam (5 μM)a1′-hydroxymidazolamKetoconazole (0.05 μM)
4′hydroxymidazolam
Testosterone (75 μM)a6β-hydroxytestosteroneKetoconazole (0.05 μM)
  • a Cocktail substrate