Herein, we first detected the effect of ATV and DXM on the expression of OATP1B1. Compared with the control and ATV groups, the protein levels of OATP1B1 were significantly decreased in the DXM and ATV+DXM groups (Figures 4A and B, *P < 0.05, **P < 0.01). Literature suggests that the expression of OATP1B1 can be upregulated when nuclear receptors LXRα are activated [10, 14]. Thus, LXRα protein expression was also decreased in DXM and ATV+DXM groups, compared with the control and ATV groups (Figures 4C and D, **P < 0.01, ***P < 0.001). These results indicated that DXM has an inhibitory effect on OATP1B1 and the upstream nuclear receptor LXRα in rat liver.