REGULATION OF MELANOGENESIS BY HUMAN UVEAL MELANOCYTES IN-VITRO

The purpose of this study was to investigate factors regulating melano genesis in cultured human uveal melanocytes. The effects of various su bstances on the melanin content, tyrosinase activity and growth of cul tured uveal melanocytes were tested. 12-O-tetradecanoyl-phorbol-13-ace tate (a protein kinase C activator) and various cAMP-elevating agents, including isobutylmethylxanthine, cholera toxin, and dibutyryl-cAMP i ncreased melanin content per culture, tyrosinase activity and cell num bers of uveal melanocytes in a dose dependent manner. Basic fibroblast growth factor (tyrosine kinase activator) stimulated growth but did n ot affect melanin content per culture of uveal melanocytes in vitro. T hese results indicate that cAMP-elevating agents and protein kinase C activator stimulate melanogenesis and growth of cultured uveal melanoc ytes. Tyrosine kinase activator stimulates growth but not melanogenesi s of cultured uveal melanocytes. (C) 1997 Academic Press Limited.