Hunt G, Todd C, Kyne S, Thody A J
Department of Dermatology, University of Newcastle upon Tyne, Royal Victoria Infirmary, UK.
J Endocrinol. 1994 Jan;140(1):R1-3. doi: 10.1677/joe.0.140r001.
While ACTH is known to induce skin pigmentation in man, its effects on cultured human melanocytes have not been investigated. Using a culture system free of artificial mitogens, we report for the first time that ACTH stimulates melanogenesis in cultured human melanocytes. While ACTH, alpha-MSH and the synthetic alpha-MSH analogue Nle4DPhe7 alpha-MSH all stimulate the activity of tyrosinase, the rate limiting enzyme in melanogenesis, and all produce a 50% increase in the melanin content of the cells at a concentration of 10(-8)-10(-7) mol/l, the shapes of the dose response curves differ: those for the MSH peptides are sigmoidal while those for ACTH are biphasic. In addition, human melanocytes are able to respond to concentrations of ACTH comparable with physiological plasma levels. We suggest that ACTH may be relatively more important than alpha-MSH as a pigmentary hormone in man and could have a physiological role in skin pigmentation.
虽然促肾上腺皮质激素（ACTH）已知可诱导人类皮肤色素沉着，但其对培养的人黑素细胞的影响尚未得到研究。我们使用不含人工促细胞分裂剂的培养系统，首次报告ACTH可刺激培养的人黑素细胞中的黑色素生成。虽然ACTH、α-促黑素（α-MSH）和合成的α-MSH类似物Nle4DPhe7α-MSH均能刺激黑色素生成中的限速酶酪氨酸酶的活性，且在浓度为10⁻⁸ - 10⁻⁷mol/L时均使细胞内黑色素含量增加50%，但剂量反应曲线的形状不同：MSH肽的曲线为S形，而ACTH的曲线为双相。此外，人黑素细胞能够对与生理血浆水平相当的ACTH浓度作出反应。我们认为，作为人类的色素生成激素，ACTH可能比α-MSH相对更重要，并且可能在皮肤色素沉着中具有生理作用。
