Melanosis
Disorders of increased melanin pigmentation that develop without preceding inflammatory disease.
Neurocutaneous Syndromes
Melanins
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.
Receptor, Melanocortin, Type 1
Facial Dermatoses
Facial dermatoses refers to various skin conditions that affect the face, causing symptoms such as redness, inflammation, papules, pustules, scaling, or pigmentation changes, which can be caused by a range of factors including genetics, infections, allergies, and environmental factors.
Felis
Panthera
Agouti Signaling Protein
A secreted protein of approximately 131 amino acids (depending on species) that regulates the synthesis of eumelanin (brown/black) pigments in MELANOCYTES. Agouti protein antagonizes the signaling of MELANOCORTIN RECEPTORS and has wide distribution including ADIPOSE TISSUE; GONADS; and HEART. Its overexpression in agouti mice results in uniform yellow coat color, OBESITY, and metabolic defects similar to type II diabetes in humans.
Colonic Diseases
Nevus, Pigmented
Jaundice, Chronic Idiopathic
A benign, autosomally recessive inherited hyperbilirubinemia characterized by the presence of a dark pigment in the centrilobular region of the liver cells. There is a functional defect in biliary excretion of bilirubin, cholephilic dyes, and porphyrins. Affected persons may be asymptomatic or have vague constitutional or gastrointestinal symptoms. The liver may be slightly enlarged, and oral and intravenous cholangiography fails to visualize the biliary tract.
Conjunctival Diseases
Hyperpigmentation
Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance.
Coyotes
Cysteinyldopa
Found in large amounts in the plasma and urine of patients with malignant melanoma. It is therefore used in the diagnosis of melanoma and for the detection of postoperative metastases. Cysteinyldopa is believed to be formed by the rapid enzymatic hydrolysis of 5-S-glutathionedopa found in melanin-producing cells.
Neuroectodermal Tumor, Melanotic
A benign, rapidly growing, deeply pigmented tumor of the jaw and occasionally of other sites, consisting of an infiltrating mass of cells arranged in an alveolar pattern, and occurring almost exclusively in infants. Its source of origin is in dispute, the various theories giving rise to its several names. (Dorland, 27th ed)