MK-0557 is a selective and orally available antagonist of the neuropeptide Y5 receptor (Ki: 1.6 nM).

AC-263093 is an NPFFR2 agonist with anxiolytic activity that increases c-Fos protein expression in the paraventricular nucleus of the hypothalamus.

Neuropeptide Y (22-36), a 15 amino acid peptide, is a fragment of Neuropeptide Y.Neuropeptide Y (NPY) is a 36 amino-acid neuropeptide that is involved in various physiological and homeostatic processes in both the central and peripheral nervous systems. NPY has been identified as the most abundant peptide present in the mammalian central nervous system, which consists of the brain and spinal cord. It is secreted alongside other neurotransmitters such as GABA and glutamate.