Pancreatic polypeptide receptor 1, also known as Neuropeptide Y receptor type 4, is a protein that in humans is encoded by the PPYR1 gene. Selective Ligands Agonists Pancreatic polypeptide Neuropeptide Y (endogenous agonist, non subtype selective) Peptide YY GR-231,118 (mixed NPY1 antagonist / NPY4 agonist, CAS# 158859-98-4) Antagonists UR-AK49 See also Neuropeptide Y receptor References External links Further reading G protein-coupled receptors