The magnetotatic bacterium Magnetospirillum magnetotacticum.
Melanocyte-stimulating hormone (MSH) is a peptide hormone produced by cells in the
intermediate lobe of the pituitary gland.
Melanocyte-stimulating hormone (MSH) stimulates the production and release
of melanin (melanogenesis) by melanocytes
in skin and hair. MSH is also produced by a subpopulation of neurons in
the arcuate nucleus of the hypothalamus.
It released into the brain by these neurons has effects on appetite and
In the skin of lower vertebrates, melanocyte-stimulating hormone stimulates the concentration of melanin granules in chromatophore.