2MeSADP-induced platelet aggregation, dense granule secretion, and TXA₂ generation in WV and G2KO mouse platelets. Washed and non–aspirin-treated WT and WV mouse platelets (A-B) or WT and G2KO mouse platelets (C-D) were stimulated with 2MeSADP (100 nM), in the absence of exogenously added fibrinogen, for 3.5 minutes at 37°C under stirring conditions, and platelet aggregation (A,C) or TXB₂ levels (B,D) were measured as described in “Materials and methods.” The data are represented as the percent maximal TXB₂ generated by 2MeSADP in WT platelets. In panels A and C, corresponding luminescence in each sample was recorded. Each bar is the average of 3 experiments ± SEM from 3 different donors.