Spinal action of dermorphin, an extremely potent opioid peptide from frog skin

Studies on the characteristics of spinally administered dermorphin, a novel heptapeptide isolated from the skin of South American Phyllomedusa frogs, indicated that this agent is 3-5000X more active spinal morphine on the hot plate, tail flick and writhing tests. This agent displays naloxone reversibility and cross tolerance to spinal morphine, and possesses all of the characteristics of a mu opiate receptor agonist.