Phosphospecificity. Whole cell extracts of control (co) or Sodium Nitroprusside (SNP) treated human platelets and extracts from control (co) or Forskolin (F) treated HepG2 cells cells were applied to SDS-PAGE and transferred to PVDF membranes. Immunoblots were probed with mab 22E11 (0.5 ug/ ml) for 1h at RT and developed by ECL (exp.time: 30 sec).