Effect of TRAP on RIPA. Washed platelets were incubated with 15 μmol/L TRAP at 37°C and fixed with paraformaldehyde at the indicated time points. The RIPA without agonist was assigned 100%. Agglutination was triggered by pooled normal plasma and 1 mg/mL ristocetin (see Materials and Methods). % agglutination (○); slope of curve (▵). Data represent a typical experiment.