Ticagrelor-mediated, adenosine receptor–independent increases in platelet VASP-P in the presence of other P2Y₁₂ antagonists. (A-B) Representative immunoblots and bar charts showing VASP-P, VASP, and α-tubulin (internal control) levels in washed platelets after incubation (60 minutes) at 37°C with vehicle (0.1% DMSO), ticagrelor (10 µM), or NECA (1 µM). Preincubation conditions were either vehicle (0.1% DMSO) + XAC (10 µM), AR-C 66096 (10 µM) + XAC (10 µM), PSB 0739 (10 µM) + XAC (10 µM), or R-138727 (10 µM) + XAC (10 µM), all at 37°C for 30 minutes; n = 7. (C-D) cAMP accumulation in washed platelets. (C) Platelets were preincubated with either ticagrelor, AR-C 66096, and R-138727 (all at 10 μM; 60 minutes) or vehicle control. Platelets were stimulated with PGE₁ (1 μM; 10 minutes) in the absence or presence of ADP (10 μM). (D) Effect of antagonists on basal cAMP levels. Incubation (60 minutes) at 37°C with vehicle (0.1% DMSO), ticagrelor (10 µM), PSB 0739 (10 µM), or R-138727 (10 µM) for 60 minutes and preincubation with XAC (10 μM; 60 minutes). All bar charts display mean and SEM. Statistical test used was 2-way ANOVA (excluding NECA data) (B). *P < .05; **P < .01; ***P < .001. Kilodaltons of molecular size markers are shown on blots.