Basal level of expression and stability of CYPs, transporters (ABC) and nuclear hormone receptors in rodent liver versus rodent hepatic cell line H411E (A, D, and G) and rodent intestinal tissue versus rodent intestinal cell line Iec-6 (B, E, and H) during passage. Basal level of expression and stability of CYPs, transporters and nuclear hormone receptors in rat primary hepatocytes over time. Data are the mean±SD. n=4 experiments conducted in duplicate.