Читать книгу Ridley's The Vulva - Группа авторов - Страница 110

Melanocytes are cells of neural crest origin that produce melanin. They appear as rounded cells with clear cytoplasm and are situated in the basal layer of the epidermis. They convert the amino acid tyrosine to melanin within membrane‐bound organelles called melanosomes. These are then transferred to keratinocytes through the melanocytes’ dendritic extensions. This transfer within the ‘epidermal melanin unit’ protects keratinocyte DNA from damage by ultraviolet radiation and certain toxins.

Melanocytes are also capable of other actions including secreting a number of signal molecules targeting keratinocytes, lymphocytes, fibroblasts, Langerhans cells, mast cells, and endothelial cells. Hormones profoundly influence human melanocyte activity, and there is a marked regional variation in the sensitivity of melanocytes to specific hormones. The vulva and perineum are sites that are very sensitive to hormonal factors.