Proteinase-activated receptor 2 (PAR2) is a G protein-coupled receptor that is cleaved by serine proteases, resulting in self-activation of the receptor by a tethered ligand. The ligand corresponds to residues 39-44 (SLIGRL in mouse PAR-2). SLIGRL-NH2 is a recombinant peptide that activates PAR2 (EC50 = ~5 μM), without requiring receptor cleavage. This peptide does not activate PAR1. Through its effects on PAR2, SLIGRL-NH2 stimulates gastric and intestinal smooth muscle contraction and induces thermal hyperalgesia in mice. SLIGRL-NH2 is used to explore signaling through PAR2 in cells and in animals.
