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.

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

SF-22 is a neuropeptide Y receptor (Y2R) antagonist that crosses the blood-brain barrier and has potential anti-inflammatory activity for the study of diseases associated with neurological disorders.