Abstract: An in vitro model of dairy cow mammary epithelial cells (DCMECs) was developed and used to study the relationship between methionine and milk protein synthesis or the lactation ability of the mammary gland. After 24 hours of in vitro culture in the presence of various concentrations (0, 0.2, 0.4, 0.8, 1.2 mmol/L and 1.6 mmol/L) of methionine, the lactation ability of DCMECs was analyzed by high performance liquid chromatography (HPLC), real-time quantitative PCR (RT-PCR), cell viability analyzer and triglyceride kit. It was found that methionine at 1.2 mmol/L had the most significant proliferationpromoting effect on DCMECs during the culture period. In addition, the highest amounts of lactose secretion, β-casein mRNA expression and triglyceride synthesis were achieved.

Key words: methionine；dairy cow mammary epithelial cells；lactose；β-casein；triglyceride；cell proliferation

摘要： 研究蛋氨酸与乳蛋白合成及乳腺泌乳能力的关系。建立体外培养的奶牛乳腺上皮细胞模型,采用高效液相色谱法、实时荧光定量PCR、细胞活力分析仪、甘油三酯试剂盒检测不同浓度蛋氨酸（0、0.2、0.4、0.8、1.2、1.6mmol/L）对体外培养24h的奶牛乳腺上皮细胞泌乳的影响。结果表明,蛋氨酸在1.2mmol/L时对体外培养的奶牛乳腺上皮细胞增殖的促进作用最明显,乳糖分泌量最高,β-酪蛋白mRNA表达量最高且甘油三酯合成最多（P〈0.01）。

关键词: 蛋氨酸;奶牛乳腺上皮细胞;乳糖;β-酪蛋白;甘油三酯;细胞增殖