[DAla2, DArg6] Dynorphin A, (1-13) (porcine) (DADAD) is an opioid peptide (dynorphinl-13, DYN) derivative found in porcine pituitary extracts. DYN is highly potent at the peripheral opioid receptors GPI and MVD, but is readily and rapidly degraded in vivo. [DAla2, DArg6] Dynorphin A, (1-13) (porcine) has some resistance to enzymatic cleavage and prevents peptide cleavage by enzymes [1] .