Tyrosinase activity in dermal nevus cells.
Tyrosinase activity in dermal nevus cells.
复制标题
真皮痣细胞中的酪氨酸酶活性。
作者：
E. Thorne;J. Mottaz;A. Zelickson
酪氨酸酶活性研究在真皮痣细胞使用的超微结构多巴技术的修改。酪氨酸酶定位于真皮浅层痣细胞的黑素体和前黑素体。在真皮中层和真皮深层的痣细胞，除了具有黑素体酪氨酸酶活性，还表现出多巴-黑色素在滑面内质网中的线性积累。具有神经样外观的痣细胞在多巴中孵育后也含有这种线性反应产物，表明与其他真皮痣细胞类似的色素细胞起源。表皮痣细胞滑面内质网酪氨酸酶活性的缺失可能与黑素体复合物信息导致的黑素自噬性降解有关。这项研究的结果支持了这一假设，即前黑素体可以直接从滑面内质网形成，而无需事先处理的高尔基体。
Tyrosinase activity was studied in dermal nevus cells using a modification of the ultrastructural DOPA technique. Tyrosinase was localized to melanosomes and premelanosomes in nevus cells of the superficial dermis. Nevus cells in the middermis and deep dermis, in addition to having melanosomal tyrosinase activity, also demonstrated linear accumulations of DOPA-melanin in the smooth endoplasmic reticulum. Nevus cells having a neuroid appearance also contained this linear reaction product after incubation in DOPA, suggesting a pigment cell origin similar to other dermal nevus cells. The absence of tyrosinase activity in the smooth endoplasmic reticulum of the superficial dermal nevus cells may be related to auto-phagic breakdown of melanin with the information of melanosome complexes. The findings of this study support the hypothesis that premelanosomes can be formed directly from the smooth endoplasmic reticulum without prior processing by the Golgi apparatus.