Dense granule secretion measurements in WT, Lyn^−/−, and SHIP-1^−/− murine platelets. Washed indomethacin-treated WT and Lyn^−/− or SHIP-1^−/− murine platelets were stimulated with 100 μM AYPGKF (A,E), 0.05 U/mL thrombin (B), 60 ng/mL CVX (C,F) or 20 μg/mL collagen (D,G) for 3 minutes at 37°C as indicated under stirring conditions. The activation of platelets was performed in a lumi-aggregometer at 37°C with stirring at 900 rotations per minute (rpm) × 100, and the secretion was measured and expressed in as nanomoles of ATP released/10⁸ platelets. The data are represented as normal secretion tracings, and the actual ATP released was represented in nanomoles and analyzed by Student t test. P ≤ .05 was considered significant.