IPA inhibits platelet activation by binding to PXR in platelets. (a) Platelet aggregation and ATP release of WT and PXR^−/− mice with or without IPA. Washed platelets from WT or PXR^−/− mice were incubated with IPA or vehicle for 20 min and then stimulated with ADP (10 μmol/L), thrombin (0.1 U/mL), or collagen (1.0 μg/mL). IPA (0.5 μmol/L) was used. Representative platelet aggregation, ATP release tracings, and summary data are presented (n = 5, per group). (b) Platelet spreading on fibrinogen of WT and PXR^−/− mice with or without IPA. IPA (0.5 μmol/L) was used. Respective pictures and the summary results of the spreading area at different time points are presented (n = 5, per group). (c) Clot retraction of WT and PXR^−/− mice with or without IPA. IPA (0.5 μmol/L) was used. Representative photographs and summary data of clot area percentage at different time points are presented (n = 5, per group; The P values are represented by ^*/^** for WT versus WT + IPA, and ^#/^## for WT + IPA versus PXR^−/− + IPA). (d) Platelet aggregation of WT and PXR^−/− mice treated with AL or IF diet induced by collagen. After a 10-day AL or IF diet (see schematic diagram in Fig. 1c), the mouse PRP was prepared for aggregation experiment. Representative platelet aggregation tracings and summary data are presented (n = 5, per group). Data are shown as mean ± SEM. ^*(#)P < 0.05; ^**(##)P < 0.01. Data were analyzed using two-way ANOVA followed by Tukey’s multiple comparisons test (a, b, c, and d).