FSLLRY-amide is a peptide antagonist of protease-activated receptor (PAR) 2 which blocks activation by trypsin (IC50 = ~50 μM) but not by the synthetic agonist SLIGRL-NH2 . It does not affect thrombin-induced activation of PAR1 or trypsin-mediated proteolysis of casein. It can be used to study PAR2 action in cells and in animals.
