Lys-{Des-Arg9]-Bradykinin is a 9 amino acid inflammatory mediating peptide that causes endothelium-dependent vasodilation and hypotensive effects. ACE inhibitors act by increasing bradykinin levels. Potent and selective bradykinin B1 receptor agonist (Ki=0.12 and >30000nM for B1 and B2 receptors, respectively). Lys-{Des-Arg9]-bradykinin is 16-fold more potent for B1 than {Des-Arg9]-bradykinin.