Potent, non-selective galanin receptor antagonist (Ki values are 1.82 and 5.1 nM at GAL1 and GAL2 respectively) that inhibits galanin (1-29) binding in rat brain in vitro (IC50 = 3 - 15 nM). Attenuates the antidepressant effects of fluoxetine and blocks galanin-induced food intake in vivo. Also exhibits weak partial agonist activity at peripheral GAL2 receptors at doses > 100 nM.

The chimeric peptide M35 [galanin (1-13)-bradykinin(2-9) amide] is a high-affinity galanin receptor ligand acting as a galanin receptor antagonist in the rat spinal cord, rat hippocampus and isolated mouse pancreatic islets. The radiolabelled M35 and performed equilibrium binding studies with [125I] M35 on the rat pancreatic beta-cell line Rin m 5F.

WAY-639889 is a small molecule compound with selective and potent inhibitory effects on neuropeptide Y-5 receptors.