MELANIN-CONCENTRATING HORMONE UPDATED FUNCTIONAL CONSIDERATIONS - FUNCTIONAL CONSIDERATIONS

The melanin-concentrating hormone (MCH) is a vertebrate neuropeptide p roduced in hypothalamic perikarya whose fibers project to most regions of the brain and into the spinal cord. Its role as a neurohypophyseal color-change hormone is peculiar to teleost fish, but recent studies in mammals suggest that MCH itself; and other peptides derived from th e same precursor may participate in multiple functions in the central nervous system, modulating behavior and the perception of sensory info rmation. Recent hybridization studies in mammals have greatly increase d our understanding of the response of the MCH system to environmental factors, such as osmotic challenge, lactation, stress, and changes in corticosteroid levels. Further studies in lower vertebrates are neede d to highlight the physiologically important functions that have led t o the structural conservation of the MCH peptide during vertebrate evo lution.