Abstract: Cao reported that melagenine extracted from human placenta was effective in the clinical treatment of vitiligo, to elucidate the possible mechanism involved, melagenine and placenta peptide were added to melanocytes in the culture, and the culture without melagenine as control. The results obtained by MTT showed that melagenine can stimulate melanoeyte proliferation, its promoting rate was 42.5%, while placenta peptide got a promoting rate of 5.9%, the difference was significant (P<0.05). The method of Oikawa was employed to measure the melanin content of melanocytes. As a resuit, cells cultured with melagenine had a melanin content of 5.5fg/cell and control cells 4.5fg/cell on average. Observation of cell ultrastrueture by transmitted electron microscope demonstrated that ceils cultured with melagenine had more melanosomes than those of control. This study proves that melagenine can stimulate melanocyte proliferation and melanin synthesis, which may be the mechanism that make it valid in clinical treatment.

Key words: Melagenine, Melanocyte, Melanin, Vitiligo