MELANOCORTINS AS FACTORS IN SOMATIC NEUROMUSCULAR GROWTH AND REGROWTH

Melanocortins, non-corticotropic fragments of adrenocorticotropic horm one, accelerate growth of the developing neuromuscular system and regr owth of damaged neurons, both in the adult and neonatal rat. Morpholog ical, electrophysiological and behavioral characteristics are all impr oved by melanocortins, which, however, vary in potency, with alpha-MSH being the most effective. Tissue substrate, dosage, critical time per iods and pattern of neuropeptide administration are all important vari ables. Melanocortins protect central neurons affecting motor behavior during development or following neuronal damage in the adult brain. Po ssible mechanisms of melanocortin action are discussed.