Emax and EC50 for CYP2C9 activity and mRNA after treatment with rifampin, phenobarbital, and phenytoin for 72 hours in either HepatoPac or monocultures in serum-free media.
| NON | BPB | Hu1624 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| HepatoPac | Monoculture | HepatoPac | Monoculture | HepatoPac | Monoculture | |||||||
| Emax | EC50 | Emax | EC50 | Emax | EC50 | Emax | EC50 | Emax | EC50 | Emax | EC50 | |
| μM | μM | μM | μM | μM | μM | |||||||
| mRNA | ||||||||||||
| Rifampin | 4.57 (0.11) | 0.13 (0.08) | 3.37 (0.37) | 1.56 (0.25) | 4.13 (0.22) | 0.99 (0.1) | ND | ND | 3.54 (0.10) | 0.23 (0.09) | ND | ND |
| Phenobarbital | 4.0 (0.25) | 254 (0.09) | 3.4 (0.33) | 389.2 (0.12) | 3.3 (0.55) | 112.8 (0.28) | ND | ND | ND | ND | ND | ND |
| Phenytoin | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND |
| Activity | ||||||||||||
| Rifampin | 3.5 (0.1) | 0.1 (0.1) | 3.7 (0.2) | 1.2 (0.1) | 3.3 (0.3) | 1.2 (0.2) | ND | ND | 3.1 (0.1) | 0.2 (0.1) | ND | ND |
| Phenobarbital | 5.1 (0.6) | 417.5 (0.1) | 3.7 | ND | 7.2 (1.6) | 848.9 (0.2) | ND | ND | 5.8 (0.8) | 449.4 (0.2) | ND | ND |
| Phenytoin | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND |
ND, curves could not be fit to a sigmoidal Emax model.
CYP2C9 activity was measured using diclofenac as the substrate and the mRNA change was measured using real-time PCR with TaqMan probes. Data shown are mean (S.E.) of three determinations.