Effects of PKG and PKA inhibitors on the cGMP-induced VASP phosphorylation in mouse platelets. Washed mouse platelets (3 × 10⁸/mL) were preincubated with Rp-pCPT-cGMPS (0.2 mM and 0.5 mM) or Rp-Br-cAMPS (0.2 mM or 0.5 mM) for 10 minutes. Platelets were then treated with 8-bromo-cGMP (100 μM) at 37°C for 10 minutes. Phosphorylation of VASP was detected by immunoblotting with monoclonal antibody 16C2 against the phosphorylated Ser²³⁹ site of VASP. Data shown are a representative of 3 independent experiments.