Isolation and characterization of neuropeptide Y from porcine intestine

The isolation and primary structure of intestinal neuropeptide Y (NPY) is described. The peptide was purified from porcine intestinal extracts using a chemical assay and radioimmunoassay for NPY. The amino acid sequence of this peptide is: Tyr-Pro-Ser-Lys-Pro-Asp-Asn-Pro-Gly-Glu-Asp-Ala-Pro-Ala-Glu-Asp-Leu-Ala- Arg-Tyr-Tyr- Ser-Ala-Leu-Arg-His-Tyr-Ile-Asn-Leu-Ile-Thr-Arg-Gln-Arg-Tyr-NH2. This the structure of intestinal NPY is identical to the NPY of brain origin.