Lyn-deficient platelets aggregate abnormally in response to thrombin receptor-activating agonists.

Lyn-deficient and wild-type murine platelets were treated with increasing concentrations of γ-thrombin (A), α-thrombin (B), or PAR4 peptide (C). Lyn-deficient platelets aggregated irreversibly only when a high concentration of agonist was used. Results are representative of 5 separate experiments.