TABLE 4 Kinetic parameters of 4′-hydroxymephenytoin formation in genotyped HLMs
Four to five human liver samples per CYP2C19 genotype were used, and S-mephenytoin to 4′-hydroxymephenytoin conversion was measured. S-mephenytoin (2.86–366.4 μM) was incubated with 0.5 mg/ml HLMs and 1 mM NADPH in 100 μl incubation mixture for 45 minutes at 37°C. A single-site Michaelis-Menten model was used to describe kinetics data. The “null” refers to CYP2C19*2 or *4 allele.