Org 2766 is one of a series of melanocortins (ACTH and related peptides) that exert trophic influences on the central and peripheral nervous system of the rat. We used acrylamide neuropathy in rats as an experimental model of peripheral neuropathies of the dying-back type in order to assess the potential therapeutic efficacy of Org 2766 in this type of nerve damage. The peptide reversed the delayed persistent deficit in sensory conduction velocity without preventing the initial loss of motor coordination. The recovery of apparently normal coordination was unaffected by the peptide, but resistance to a second toxic challenge suggested that recovery was more complete in the peptide-treated rats. The finding that Org 2766 improved the quality of the repair following acrylamide neuropathy, together with previous studies showing beneficial effects in neuropathies caused by cisplatin or diabetes and after mechanical trauma, strongly suggests that Org 2766 may be beneficial in the treatment of various conditions in which the nervous system has sustained damage.