mesotocin

例句：

1. 1. The melanin-concentrating hormone is responsible for the regulation of pigmentation in the skin.
   黑色素聚集激素负责调节皮肤的色素沉着。
2. 2.Melanocyte-stimulating hormone has been shown to stimulate the growth of melanocytes and promote melanin production.
   黑色素细胞刺激激素已被证明能刺激黑色素细胞生长并促进黑色素产生。
3. 3.Melanotropin is a naturally occurring protein that plays a crucial role in the regulation of melanin synthesis.
   黑色素生成素是一种自然存在的蛋白质，在黑色素合成的调节中起着关键作用。