TgCYP3A4/hPXR mice were treated with purified diet (control) or modified diet with 100 mg/kg RIF for 6 days. On the 7th day, TgCYP3A4/hPXR mice were administered 50 mg/kg APV orally by gavage, and blood samples were collected at 0.25, 0.5, 1, 2, 4, 8, 18 hours after the treatment. (A) Expression of hepatic and intestinal CYP3A in TgCYP3A4/hPXR mice after 6 days treatment with RIF diet. Liver and intestine microsomes were prepared and analyzed by western blot. The monoclonal antibody against CYP3A4 (mAb 275-1-2) recognizes human CYP3A4 but not mouse Cyp3a or other liver proteins. The monoclonal antibody against Cyp3a (mAb 2-13-1) reacts with both mouse Cyp3a and human CYP3A4. Human liver microsome (HLM) and human intestine microsomes (HIM) served as positive control for CYP3A4. GAPDH was used as loading control. (B) Time course of serum APV concentration (nM) was expressed as means (pooled sample, n = 3). APV was detected by LC-MS/MS.