EFFECT OF MELATONIN ON MAMMALIAN EPIDERMAL MELANOCYTES

[摘要] The effect of large doses of melatonin on the melanocytes and melanin in the skin of the anterior abdominal wall has been studied in pure black and pure red male guinea pigs. The hormone was injected subcutaneously, once daily, for one month. No grossly observable changes in the pigmentation of the skin occurred following the hormone treatment. Microscopically. there was no definite evidence that melatonin caused the melanin granules within the melanocytes to change their position. The length and complexity of the dendritic processes of the melanocytes remained unaltered in the majority of the animals. The significance of these findings in relation to the action of this hormone on the pigment cells in the frog was discussed.