Apparently these peptides act as natural analgesics (pain-killers) and their action mimics that of morphine and other opiates. At present it is thought that the morphine-like effects are due to aromat...Apparently these peptides act as natural analgesics (pain-killers) and their action mimics that of morphine and other opiates. At present it is thought that the morphine-like effects are due to aromatic side chains on phenylanine and tyrosine which mimic a similar sturcture on morphine. Apparently, it does not make much difference whether the enkephalin contains methionine or leucine at the acid end of the peptide.
