Opiorphin (OPI)

Opiorphin is an endogenous chemical compound first isolated from human saliva. Initial research with mice shows the compound has a painkilling effect greater than that of morphine. It works by stopping the normal breakdown of natural pain-killing opioids in the spine, called enkephalins. It is a relatively simple molecule consisting of a five-amino acid polypeptide, Gln-Arg-Phe-Ser-Arg. Opiorphin pentapetide originates from the N-terminal region of the protein PROL1 (proline rich, lacrimal 1). Opiorphin, inhibits 2 enkephalin-catabolizing enzymes, neutral ecto-endopeptidase (MME) and ecto-aminopeptidase N (ANPEP). Human Opiorphin, a natural antinociceptive modulator of opioid-dependent pathways.Opiorphin, found in human saliva, is an enkephalinase inhibitor, i.e. it prevents the metabolism of enkephalins.