Abstract
Summary
1. Autoxidation of dopa in vitro was more strongly catalyzed by cupric ions than by any of the other heavy metallic salts investigated. The order of catalytic activity was Cu > Co> Ni> Mn> Pb> Fe.
2. Black and grey hair of rabbits, guinea pigs and rats generally, but not always, contained more copper than white hair of the same individual. In guinea pigs, red-brown hair contained more iron than white hair.
3. Analysis of the separated layers of human skin showed a considerably higher copper content in the epidermis than in the coriuum.
4. Melanin from mouse melanomas had a copper content 4 to 13 times higher than the tumor from which it was prepared.
5. The theory is advanced that copper plays a role its a local catalyst in mammalian pigmentation.
Get full access to this article
View all access options for this article.