Potent neuropeptide Y (NPY) Y5 receptor agonist (pEC50 values are 7.82, 6.28, 6.44 and > 6 at rat Y5, Y4, Y1 and Y2 receptors respectively) that displays > 26-fold, > 1000-fold and > 1000-fold selectivity over Y1, Y2 and Y4 receptors respectively. Induces hyperphagia, body weight gain, adiposity, hypercholesterolemia, hyperinsulinemia and hyperleptinemia in vivo. Orally active.

GW438014A is a potent, selective antagonist of the NPY-Y5 receptor, effectively inhibiting food consumption and curbing body weight gain in obese rodents.

AC-099 hydrochloride is a selective full agonist of the neuropeptide FF2 receptor NPFF2R (EC50=1189 nM) and partial agonist function of the neuropeptide FF1 receptor NPFF1R (EC50=2370 nM) that reverses opioid-induced nociceptive sensitization, and may be used to study neurological.