II. Physiology: Hormonal Control

  1. Melanocyte Stimulating Hormone (MSH)
    1. Peptide Hormones secreted by the intermediate lobe of the anterior piuitary gland
    2. Stimulates Melanin release and dispersal from Melanocytes
  2. Melanocyte Stimulating Hormone Releasing Factor
    1. Hypothalamic peptide that promotes MSH release
  3. MSH Release-Inhibiting Hormone
    1. Hypothalamic peptide inhibits MSH release

III. Physiology: Melanocytes

  1. Located in Basal Cell Layer of skin
  2. Melanosome organelles are produced by Melanocytes
    1. Melanosome transferred to Keratinocytes
  3. Melanin (brown pigment) produced within Melanosome
    1. Tyrosine converted to Melanin
    2. Melanin screens out sunlight ultraviolet rays
  4. Hyperpigmentation
    1. Increased Melanosomes
      1. Sun Exposure
      2. Hormonal control
        1. See Hyperpigmentation in Pregnancy
    2. Darker Skin Color in certain ethnic groups
      1. Same number of Melanosomes as lighter skin
      2. Darker skin results from larger Melanosomes
    3. Other factors affecting pigmentation
      1. Skin vascularity
      2. Presence of Carotene
      3. Thickness of Stratum Corneum

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Related Studies

Ontology: Melanins (C0025196)

Definition (CHV) a kind of substance that gives color to skin and eyes
Definition (CHV) a kind of substance that gives color to skin and eyes
Definition (NCI_NCI-GLOSS) A pigment that gives color to skin and eyes and helps protect it from damage by ultraviolet light.
Definition (CSP) amorphous, nonproteinaceous pigment responsible for the brown hue of eyes, skin, hair, various tumors, and certain internal structures including the substantia nigra of the brain.
Definition (MSH) Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.
Concepts Biologically Active Substance (T123) , Organic Chemical (T109)
MSH D008543
SnomedCT 59094002
LNC LP15724-5, MTHU007384
English Melanin, Melanins, Melanins [Chemical/Ingredient], melanins, melanin, Melanin (substance)
Swedish Melaniner
Czech melaniny
Finnish Melaniinit
Japanese メラニン, メラニン色素
French Mélanines, Mélanine
Italian Melanina, Melanine
Polish Melaniny
Spanish melanina (sustancia), melanina, Melaninas
German Melanine
Portuguese Melaninas

Ontology: melanocyte (C0025201)

Definition (NCI_NCI-GLOSS) Cells in the skin and eyes that produce and contain the pigment called melanin.
Definition (CSP) dendritic pigment cells of the epidermis that synthesize tyrosinase, and within their melanosomes the pigment melanin is synthesized; they control long term morphological skin color changes.
Definition (MSH) Mammalian pigment cells that produce MELANINS, pigments found mainly in the EPIDERMIS, but also in the eyes and the hair, by a process called melanogenesis. Coloration can be altered by the number of melanocytes or the amount of pigment produced and stored in the organelles called MELANOSOMES. The large non-mammalian melanin-containing cells are called MELANOPHORES.
Concepts Cell (T025)
MSH D008544
SnomedCT 9683001
English Melanocytes, melanocytes, Melanocyte, Melanocyte (cell), melanocyte
French Mélanocyte, Mélanocytes
Swedish Melanocyter
Czech melanocyty
Finnish Melanosyytit
Latvian Melanocīti
Polish Melanocyty
Norwegian Melanocytter
Spanish melanocito (célula), melanocito, Melanocitos
German Melanozyten
Italian Melanociti
Dutch Melanocyt, Melanocyten
Portuguese Melanócitos

Ontology: Melanosomes (C0025213)

Definition (GO) A tissue-specific, membrane-bounded cytoplasmic organelle within which melanin pigments are synthesized and stored. Melanosomes are synthesized in melanocyte cells. [GOC:jl, PMID:11584301]
Definition (MSH) Melanin-containing organelles found in melanocytes and melanophores.
Definition (CSP) granules within melanocytes that contain tyrosinase and synthesize melanin.
Concepts Cell Component (T026)
MSH D020460
English Melanosomes, melanosome, Melanosome, melanosomes
French Mélanosome, Mélanosomes
Swedish Melanosomer
Czech melanozómy
Finnish Melanosomit
Latvian Melanosomas
Polish Melanosomy
Norwegian Melanosomer
Portuguese Melanossomos, Melanossomas
German Melanosomen
Italian Melanosomi
Dutch Melanosomen, Melanosoom
Spanish Melanosomas

Ontology: Melanocyte stimulating hormone (C0026667)

Definition (MSH) Peptides with the ability to stimulate pigmented cells MELANOCYTES in mammals and MELANOPHORES in lower vertebrates. By stimulating the synthesis and distribution of MELANIN in these pigmented cells, they increase coloration of skin and other tissue. MSHs, derived from pro-opiomelanocortin (POMC), are produced by MELANOTROPHS in the INTERMEDIATE LOBE OF PITUITARY; CORTICOTROPHS in the ANTERIOR LOBE OF PITUITARY, and the hypothalamic neurons in the ARCUATE NUCLEUS OF HYPOTHALAMUS.
Definition (CSP) peptide hormones secreted by the intermediate lobe of the pituitary that stimulate melanin release and dispersal; also found in the brain where they are presumed to play a signaling role.
Concepts Pharmacologic Substance (T121) , Neuroreactive Substance or Biogenic Amine (T124) , Hormone (T125) , Amino Acid, Peptide, or Protein (T116)
MSH D009074
SnomedCT 46015007
LNC LP31744-3
English Melanophore-Stimulating Hormone, Melanotropin, melanocyte stimulating hormone, Melanocyte Stimulating Hormones, Melanophore Stimulating Hormone, Melanocyte stimulating hormone, MELANOCYTE-STIMULATING HORMONE, MELANOTROPIN, MSH - Melanocyte stim horm, melanophore dilating principle, melanophore stimulating hormone, intermedin, Melanocyte-stimulating hormone, Melanocyte-Stimulating Hormones [Chemical/Ingredient], melanocyte stimulating hormone (MSH), melanocyte-stimulating hormone, msh, melanotropin, MSH - Melanocyte stimulating hormone, Melanocyte stimulating hormone (substance), Melanocyte Stimulating Hormone, Melanocyte-Stimulating Hormones, MSH, MSH (Melanocyte-Stimulating Hormones)
Portuguese Hormônios Estimuladores de Melanócitos, MSH, Melanotropina
French Hormones mélanostimulantes, Hormones mélano-stimulantes, Hormones mélanotropes, Hormones stimulant les mélanocytes, MSH (Melanocyte stimulating hormone), Hormone mélanotrope, Mélanostimuline, Mélanotropine
Swedish Melanocytstimulerande hormoner
Czech intermedin, melanofory stimulující hormon, melanotropin, melanocyty stimulující hormony, MSH
Spanish Hormonas Estimuladoras de los Melanocitos, hormona melanocitoestimulante, melanotrofina, MSH, Hormonas Estimulantes de los Melanocitos, HEM, Hormonas Estimuladoras de Melanocitos, hormona estimulante de los melanocitos (sustancia), hormona estimulante de los melanocitos, melanotropina, Melanotropina
Finnish Melanosyyttejä stimuloivat hormonit
Italian Ormone stimolante i melanociti, MSH (Ormoni stimolanti i melanociti), Melanotropina, MSH, Ormoni melanocito-stimolanti, Ormoni stimolanti i melanociti
Croatian Not Translated[Melanocyte-Stimulating Hormones]
Polish Hormony melanotropowe, Hormony stymulujące melanocyty, Melanotropiny, MSH, Hormony pobudzające melanocyty
Japanese メラノリベリン, MSH放出ホルモン, メラニン細胞刺激ホルモン放出ホルモン, メラニン細胞刺激ホルモン, メラノサイト刺激ホルモン, メラノトロピン, 色素細胞刺激ホルモン, 黒色素胞刺激ホルモン
Norwegian Melanocyttstimulerende hormoner, MSH, MSH, melanocyttstimulerende hormoner
German MSH, Melanotropin, Melanozyten-stimulierende Hormone, Intermedin

Ontology: MSH Release-Inhibiting Hormone (C0026669)

Definition (MSH) A hypothalamic tripeptide, enzymatic degradation product of OXYTOCIN, that inhibits the release of MELANOCYTE-STIMULATING HORMONES.
Concepts Pharmacologic Substance (T121) , Hormone (T125) , Amino Acid, Peptide, or Protein (T116)
MSH D009075
English H-Pro-Leu-Gly-NH2, Melanocyte-Stimulating Hormone Release-Inhibiting Factor, Melanostatin, MIF-1, MIF-I, Oxytocin (7-9), Pro-Leu-Gly-NH2, Pro-Leu-Glyamide, Prol Leu Gly NH2, Prol-Leu-Gly-NH2, Prolyl Leucyl Glycinamide, Prolyl-Leucyl-Glycinamide, Prolylleucylglycinamide, MSH Release-Inhibiting Factor, MSH Release-Inhibiting Hormone, Melanocyte-Stimulating Hormone Release-Inhibiting Hormone, MSH RELEASE INHIB FACTOR, MELANOCYTE STIMULATING HORMONE RELEASE INHIB HORMONE, MELANOCYTE STIMULATING HORMONE RELEASE INHIB FACTOR, MSHRIH, MSH Release-Inhibiting Hormone [Chemical/Ingredient]
Swedish MSH-hämmande hormon
Czech hormon inhibující uvolňování MSH
Finnish MSH:n vapautumista estävä hormoni
French Peptide MIF-1, Ocytocine (7-9), Pro-Leu-Gly-NH2, Hormone inhibitrice de la libération de MSH, Mélanostatine, Peptide MIF-I, MSH-IH, Oxytocine (7-9), Prolyl-Leucyl-Glycinamide, Facteur inhibiteur de la libération de MSH, MSH-IF
Spanish Factor Inhibidor de Liberación MSH, Hormona Inhibidora de la Liberación de MSH, Factor Inhibidor de Liberación HEM, Hormona Inhibidora de la Liberación de HEM, Prolil-Leucil-Glicinamida, Hormona Inhibidora de Liberación de Hormona Melanocito-Estimulante
Polish Hormon hamujący uwalnianie melanotropiny, Melanostatyna
Japanese MSH放出抑制因子, メラニン細胞刺激ホルモン放出抑制因子, メラノスタチン, MSH放出抑制ホルモン, プロリル-ロイシル-グリシンアミド, メラニン細胞刺激ホルモン放出抑制ホルモン
Norwegian MIF-1, Prolyl-leucyl-glycinamid, Melanocytthemmende hormon, Pro-Leu-glyamid, Prolylleucylglycinamid, Melanostatin, Oksytocin (7-9), Pro-Leu-Gly-NH2, MIF-I, Prol-Leu-Gly-NH2, H-Pro-Leu-Gly-NH2
German MSH-Release-Inhibiting-Hormon, MSH-Release-inhibierender Faktor, Melanozytenstimulierendes Hormon, Release-inhibierender Faktor, Prolyl-Leucyl-Glycinamid
Italian Ormone inibitore del rilascio dell'ormone MSH
Portuguese Fator Inibidor da Liberação de MSH, Hormônio Inibidor da Liberação de Hormônios Estimuladores de Melanócito, Hormônio Inibidor da Liberação de MSH, Prolil-Leucil-Glicinamida

Ontology: Melanocyte stimulating hormone releasing factor (C0312443)

Concepts Hormone (T125) , Amino Acid, Peptide, or Protein (T116) , Pharmacologic Substance (T121)
SnomedCT 43440003, 32462006
Spanish preparado de factor liberador de MSH, preparado de MRF, factor liberador de melanotrofina (producto), preparado de factor liberador de melanotropina, factor liberador de melanotrofina, preparado de factor liberador de melanotrofina (producto), preparado de factor liberador de melanotrofina, factor liberador de MSH, factor liberador de hormona estimulante de los melanocitos (sustancia), factor liberador de hormona estimulante de los melanocitos, preparado de factor liberador de melanotrofina (sustancia)
English mrf, melanocyte stimulating hormone releasing factor (MRF), Melanocyte stimulating hormone releasing factor, MRF, MRF preparation, Melanocyte stimulating hormone releasing factor preparation, Melanocyte stimulating hormone releasing factor (substance), Melanocyte stimulating hormone releasing factor preparation (product), Melanocyte stimulating hormone releasing factor preparation (substance)