title: Effect of alpha-MSH on the tyrosinase activity and the rate of melanin accumulation of melanoma cells in vitro.
abstract: A stimulation of the tyrosinase activity was observed when melanoma cells isolated from transplantable mouse melanomas were incubated at 37 degrees C for 6 h in the presence of 1-10 X 10(-6) M alpha-MSH. All strains of mouse melanomas studied (B-16, Cloudman S-91 and Harding-Passey), exhibited similar responses. It was also observed that the intact cellular structure of melanoma cells was not required for the ability to respond to alpha-MSH. The stimulation of the enzymic activity was accompanied by an increase of the rate of incorporation of radioactivity into melanin from L-[U-14C]tyrosine, indicating an enhanced melanogenesis of tumour cells under in vitro conditions.
mesh_terms: D000818:Animals; D004156:Catechol Oxidase / Q000378:metabolism*; D002478:Cells, Cultured; D066298:In Vitro Techniques; D007980:Levodopa / Q000378:metabolism; D008543:Melanins / Q000378:metabolism*; D009074:Melanocyte-Stimulating Hormones / Q000494:pharmacology*; D008545:Melanoma / Q000201:enzymology / Q000378:metabolism*; D051379:Mice; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D009374:Neoplasms, Experimental / Q000201:enzymology / Q000378:metabolism; D011691:Puromycin / Q000494:pharmacology; D014443:Tyrosine / Q000378:metabolism
chemical_list: D008543:Melanins; D014443:Tyrosine; D007980:Levodopa; D011691:Puromycin; D009074:Melanocyte-Stimulating Hormones; D004156:Catechol Oxidase; D014442:Monophenol Monooxygenase