环磷酸腺苷促进泰和乌骨鸡皮肤黑色素细胞黑色素合成

Cyclic Adenosine Monophosphate Stimulates Melanogenesis in In Vitro Melanocytes from Skins of Taihe Silky Fowls

该实验旨在研究环磷酸腺苷(cyclic adenosine monophosphate,c AMP)作为α-黑色素细胞刺激素(α-melanocyte stimulating hormone,α-MSH)-黑素皮质素受体1(melanocortin 1 receptor,MC1R)通路的下游信号分子对泰和乌骨鸡皮肤黑色素细胞黑色素合成的影响。利用体外培养的泰和乌骨鸡皮肤黑色素细胞,观察不同浓度c AMP(0、1×10–5、1×10–4、1×10–3 mol/L)及其抑制剂、腺苷酸环化酶(adenylate cyclase,AC)抑制剂对乌骨鸡皮肤黑色素细胞酪氨酸酶(tyrosinase,TYR)活性和黑色素含量的影响。结果表明,与不添加c AMP的对照组相比,不同浓度的c AMP均极显著提高泰和乌骨鸡皮肤黑色素细胞TYR活性(P<0.01),10–4 mol/L组提高的幅度最大。不同浓度的c AMP可不同程度地促进黑色素细胞黑色素的合成,1×10–5 mol/L和1×10–4 mol/L组黑色素含量分别显著(P<0.05)和极显著(P<0.01)高于不添加c AMP的对照组。c AMP抑制剂Rp-c AMPS预处理黑色素细胞显著抑制c AMP(1×10–4 mol/L)作用下酪氨酸酶活性(P<0.01)和黑色素含量的升高(P<0.05)。Rpc AMPS和AC抑制剂NKY80预处理黑色素细胞均显著抑制α-MSH(2.5μg/m L)引起的TYR活性、c AMP含量和黑色素含量的升高(P<0.01或P<0.05)。c AMP作为α-MSH-MC1R信号通路中的第二信使或下游信号分子在泰和乌骨鸡皮肤黑色素细胞黑色素的合成中发挥重要作用,其浓度的升高可提高泰和乌骨鸡皮肤黑色素细胞酪氨酸酶活性以及黑色素的合成。

This study was conducted to investigate the effect of cyclic adenosine monophosphate（cA MP） on melanin synthesis in skin melanocytes of Taihe silky fowls. The skin melanocytes of Taihe silky fowls were cultured in vitro with cA MP at a concentration of 0, 1×10–5, 1×10–4, 1×10–3 mol/L or pretreated with cA MP inhibitor（Rp-cA MPS） or adenylate cyclase（AC） inhibitor NKY80 prior to the addition of cA MP, and then the tyrosinase activity and melanin contents were determined. cA MP at various concentrations tested in the present study significantly increased TYR activityin silky fowl skin melanocytes with the highest tyrosinase activity in the 1×10–4 mol/L cA MP-treated cells（P〈0.01）. cA MP supplemented at all concentrations used in the present study stimulated pigmentation in skin melanocytes with different extents. Melanin content in 1×10–5 mol/L or 1×10–4 mol/L cA MP-treated cells were higher than that in control without cA MP supplementation（P〈0.05 or P〈0.01）. However, pretreatment with Rp-cA MPS significantly inhibited the stimulatory effects of cA MP（1×10–4 mol/L） on tyrosinase activity（P〈0.01） and melanin synthesis in skin melanocytes（P〈0.05）. Moreover, both pretreatments with Rp-cA MPS or AC inhibitor NKY80 significantly inhibited the stimulatory effects of α-melanocyte stimulating hormone（α-MSH）（2.5 μg/mL） on tyrosinase activity, cA MP formation and melanin synthesis in skin melanocytes of Taihe silky fowls（P〈0.05 or P〈0.01）. In conclusion, cA MP, as the second messenger or downstream signal molecule in α-MSH-MC1 R（melanocortin 1 receptor） signaling pathway, plays crucial role in melanogenesis, the tyrosinase activity and melanin content in skin melanocytes of Taihe silky fowls increase with the increasement of cA MP concentration at the suitable range.