Regulation of growth and melanogenesis of uveal melanocytes

We have developed methods for the isolation, cultivation, and investigation of human uveal melanocytes (UM). Uveal melanocytes grow well and produce m elanin in vitro in the presence of basic fibroblast growth factor (bFGF), c yclic adenosine monophosphate-elevating agents, and serum. Cultured UM resp ond to various factors. Certain growth factors (bFGF and hepatocyte growth factor, etc.), endothelin, adrenergic beta(2)-receptor agonists, and some p rostaglandins (EP2-receptor agonists and certain TP-receptor agonists) stim ulate, while transforming growth factor-beta(2), interleukin-6, and choline rgic agonists inhibit melanogenesis and/or growth of UM in vitro. alpha-Mel anocyte-stimulating hormone, adrenocorticotropic hormone, various sex hormo nes, and prostaglandin F-2 alpha showed no effect on the growth and melanog enesis of cultured UM, The stability of UM in vivo may be controlled by the se factors. Disturbance of this balance may lead to certain rare pathologic pigmentary changes of the iris, UM are relatively stable in vivo; they usu ally do not respond (proliferate or show dynamic changes in melanogenesis) to various environmental factors, The differences of the in vivo behavior b etween uveal and epidermal melanocytes may be determined by both cellular f actors and environmental factors.