Peptide YY (PYY) also known as peptide tyrosine tyrosine or pancreatic peptide YY, is a 36aa peptide released by cells in the ileum and colon in response to feeding. In the blood, gut, and other elements of periphery, PPY acts to reduce appetite. When injected directly in the CNS, PYY is also anorexigenic.Human: H-Tyr-Pro-Ile-Lys-Pro-Glu-Ala-Pro-Gly-Glu-Asp-Ala-Ser-Pro-Glu-Glu-Leu-Asn-Arg-Tyr-Tyr-Ala-Ser-Leu-Arg-His-Tyr-Leu-Asn-Leu-Val-Thr-Arg-Gln-Arg-Tyr-NH2 or H-YPIKPEAPGEDASPEELNRYYASLRHYLNLVTRQRY-NH2