Table 2

Interindividual variation in CYP3A4 basal activity and induction by rifampin in primary cultures of human hepatocytes

Donor0 μM2-a2 μM10 μM20 μM50 μM
HL-N0953.312-b 8.359.5711.17N.D.
HL-N0985.4110.678.249.63N.D.
HL-N1003.198.778.138.90N.D.
H2321.89N.D.N.D.N.D.8.01
H2333.368.0912.247.6411.38
H2491.847.787.666.967.48
H2540.643.393.826.323.98
  • N.D., not determined.

  • 2-a  Final concentrations of rifampin in primary cultures of human hepatocytes.

  • 2-b  Human hepatocytes were treated with rifampin for 3 days. Microsomes were prepared 24 hr after the last treatment, and the CYP3A4 activity was determined by measuring testosterone 6β-hydroxylase activity (nmol/mg/min) as described previously (Pearce et al., 1996).