F2RL3 and Stroke: Supplemental Figure 20 shows, importantly, that P2Y12-mediated platelet aggregation was equally blocked in hPAR4Ala/Ala and hPAR4Thr/Thr mice using this treatment regimen. This implies ticagrelor-mediated suppression of PAR4 signaling is required for its protective effect in murine stroke. Moreover, increasing the concentration of ticagrelor 2-fold to 400 mg/kg did not change IS outcomes in hPAR4Thr/Thr mice compared with vehicle-treated mice (Supplemental Figure 21).