melanocyte-stimulating hormone n either of two vertebrate hormones of the pituitary gland that darken the skin by stimulating melanin dispersion in pigment-containing cells abbr. MSH called also intermedin, melanophore-stimulating hormone, melanotropin
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(MSH)
a hormone synthesized and released by the pituitary gland. In amphibians MSH brings about colour changes in the skin but its physiological role in humans is uncertain.
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melanophore-stimulating hormone (MSH) a melanotropic peptide that is an anterior pituitary hormone derived from pro-opiomelanocortin. Types are designated α, β, and γ1 to γ3. The acylated forms cause dispersion of pigment granules of melanocytes, producing a rapid change in skin coloration, while the non-acylated forms are neurotransmitters. α-MSH is identical to the N-terminal 13 residues of corticotropin, and β-MSH to the C-terminal 18 residues of γ-lipotropin. Immunoreactive “β-MSH†in humans consists of β- and γ-lipotropin. Administration of α-MSH or elevation of corticotropin in humans causes a slight increase in melanization. Called also intermedin and melanotropin.Medical dictionary. 2011.