Aggregation tracings of platelets lacking PLCβ2/β3. Murine platelets lacking PLCβ2/β3 were analyzed after agonist stimulation in a Lumi-dual Aggregometer. Platelets lacking both PLCβ2 and PLCβ3 have a defect in aggregation in response to ADP and low doses of thrombin and exhibit impairment in the second wave of aggregation. Results are representative of 9 experiments performed to date.