Wikipedia
Amidorphin
Amidorphin is an endogenous, C-terminally amidated, opioid peptide generated as a cleavage product of proenkephalin A that is widely distributed in the mammalian brain, with particularly high concentrations found in the adrenal medulla, posterior pituitary, and striatum. In some brain areas, amidorphin is extensively further reduced into smaller fragments, such as the non-opioid peptide amidorphin-(8-26) which lacks the N-terminal [[Met-enkephalin|[Met]enkephalin]] sequence of amidorphin; accordingly, [Met]enkephalin may also be a cleavage product of amidorphin.