Effects of HPA axis-related hormones on melanin synthesis in vitro.

<p><b>A</b>: Measurement of melanin contents in normal human epidermal melanocytes (NHEMs) after treatment with 50 nM α-MSH or 1 µM DEX for 72 h. <b>D</b>: Measurement of melanin contents in B16F10 cells after treatment with 50 nM α-MSH or 1 µM DEX for 72 h. <b>B–C</b>: The mRNA expression levels of MITF and TYR in NHEMs after treatment with 50 nM α-MSH or 1 µM DEX for 24 h. <b>E–F</b>: The mRNA expression levels of MITF and TYR in B16F10 cells after treatment with 50 nM α-MSH or 1 µM DEX for 24 h. The expression levels of each gene were normalized against β-Actin or GAPDH then calculated as fold change using the comparative 2^-ΔΔCT method. Data are combined from three separate experiments and showed in mean ± SEM, and the data were analyzed by one-way ANOVA with Tukey's post hoc test. * <i>P<0.05</i>, ** <i>P<0.01</i>, *** <i>P<0.001</i>, compared with control; ^&&<i>P<0.01</i>, compared with α-MSH.