Wirestrand LE, Hansson C, Rosengren E, Rorsman H.
DOI: 10.2340/0001555565345348

The urinary excretion of 2 melanocyte metabolites was studied in normal people of different skin type. The sulphur-free indole derivative 6-hydroxy-5-methoxyindole-2-carboxylic acid was excreted in larger quantities by people with genetically dark skin, whereas the excretion of 5-S-cysteinyldopa was not related to pigment type. No correlation between 5-S-cysteinyldopa and 6-hydroxy-5-methoxyindole-2-carboxylic acid excretion emerged.