中文摘要：

目的：探索不同剂量的L-酪氨酸对羊驼黑素细胞增殖以及酪氨酸酶mRNA表达的影响。方法：体外培养正常羊驼皮肤黑素细胞，显微镜下观察不同剂量的L-酪氨酸（100μmol／L、200μmol／L、300μmol／L、400μmol／L）对羊驼皮肤黑素细胞增殖的影响，利用实时荧光定量PCR技术分析不同剂量L-酪氨酸对酪氨酸酶mRNA的表达量的影响。结果：研究结果显示：在培养的黑素细胞中添加了不同剂量L-酪氨酸3d后，镜检观察，黑素细胞数量相比较空白对照组有所减少，酪氨酸酶mRNA表达量增加且显著高于对照组（P〈0．05），在200μmol／L时，酪氨酸酶mRNA表达量达到最高峰值。结论：L-酪氨酸能诱导羊驼皮肤黑素细胞酪氨酸酶mRNA表达量增高。

英文摘要：

Objective： To study the effect of different dose L-tyrosine on Meianocyte count and mRNA expression of tyrosinase in Alpaca skin melanocytes. Methods ： Normal Alpacga skin melanocytes were isolated and cuhured till logarithmic period of seventh passage, and then different concentrations of L-Tyrosine （100 μmoL/L, 200 μmol/L, 300 μmol/L, 400μmol/L） were added to study the effects on Meianocyt count, to examine mRNA expression of tyrosinase by QRT-PCR. Results：In the cells after 3 days L-tyrosine treatment, melanocyte count somewhat grew downwards and the expression of tyrosinase mRNA increased compared with those of untreated cells （ P 〈 0.05 ） , especially when the concentration is 200 μmol/L, tyrosinase activity reaches peak value. Conclusion： L-tyrosine can make the mRNA expression of tyrosinase increase.