Quantification of the effect of Q3GA on the intestinal and hepatic protein levels, assessed by western blotting. Quantification of western blotting results revealed protein expression levels of (A) CYP3A1, (B) CYP3A2, (C) UGT1A1, (D) SULT1A1, (E) GSTM1, (F) OATP2B1/OATP1B2, (G) P-gp, (H) BCRP, (I) MRP2, (J) PXR, and (K) CAR measured in the small intestine and liver of rats. Values are expressed as the mean ± standard deviation (n=3). aP<0.05, bP<0.01, cP<0.001 vs. control; dP<0.05, eP<0.01, fP<0.001 vs. inhibitor group (KET/VER). Q3GA-L, low-dose Q3GA (2.5 mg/kg); Q3GA-M, middle-dose Q3GA (5 mg/kg); Q3GA-H, high-dose Q3GA (10 mg/kg). BCRP, breast cancer resistance protein; CAR, constitutive androstane receptor; CsA, cyclosporin A; CYP, cytochrome P450; GSTM, glutathione-S-transferase-µ; KET, ketoconazole; MRP2 multidrug resistance-associated protein 2; OATP, organic anion transporting polypeptide; P-gp, P-glycoprotein; PXR, pregnane X receptor; Q3GA, quercetin-3-O-β-D-glucoside; SULT, sulfotransferase; UGT, UDP glucuronosyltransferase; VER, verapamil.