There is evidence that L‐tyrosine and L‐dihydroxyphenylalanine (L‐DOPA), besides serving
as substrates and intermediates of melanogenesis, are also bioregulatory agents acting not …

We describe results demonstrating the positive regulation of melanogenesis by two
substrates of the melanogenic pathway. We have found that L-tyrosine and L …

Some amino acids have bioregulatory functions, which far exceed those of precursors for
proteins or of substrates for specific enzymes. Two of these amino acids, L-tyrosine and L …

Melanins are natural pigments of skin, hair and eyes and can be classified into two main
types: brown to black eumelanin and yellow to reddish-brown pheomelanin. Biosynthesis of …

In cultured cells of the Bomirski Ab amelanotic hamster melanoma line, the substrates of
tyrosinase, L‐tyrosine, and L‐DOPA induce the melanogenic pathway. In this report, we …

More than 15 years ago, we have proposed that melanocytes are sensory and regulatory
cells with computing capability, which transform external and/or internal signals/energy into …

A comparative study of 14C-labeled l-phenylalanine and 3H-labeled l-tyrosine uptake in
cultures of human melanocytes (n= 8) and keratinocytes (n= 2) identified a significantly more …

Melanocyte‐stimulating hormone (α‐MSH) increases cytosolic levels of cAMP as well as
tyrosinase activity in murine melanocytes. These activities depend upon the presence of …

alpha-Melanocyte-stimulating hormone (alpha-MSH) reversibly darkens frog skins by
stimulating melanosome movement (dispersion) within melanophores. Heat-alkali treatment …

Cutaneous melanin pigment plays a critical role in camouflage, mimicry, social
communication, and protection against harmful effects of solar radiation. Melanogenesis is …