共轭亚油酸对体外培养的猪骨骼肌肌纤维类型组成的影响  

Effect of Conjugated Linoleic Acid on the Composition of Myofiber Types in Skeletal Muscle Cells of Pigs in Vitro

作　　者：黄金秀[1] 杨飞云[1] 刘作华[1] 江山[1] 肖融[1] 

机构地区：[1]重庆市畜牧科学院,重庆402460

出　　处：《畜牧兽医学报》2010年第3期295-300,共6页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：国家"十一五"科技支撑计划(2007BAD51B04;2007BAD51B06);重庆市自然科学基金重点项目(2008BA1013;2009BA1078)

摘　　要：旨在研究共轭亚油酸（conjugated linoleicacid，CLA）对体外培养的猪骨骼肌肌纤维类型组成的影响规律。以体外培养的原代猪骨骼肌卫星细胞为材料，在卫星细胞向肌纤维转化时添加不同水平CLA（0、50、100、150、200μg·mL-1），处理后第4、8和12天，分别采用相对定量RT—PCR测定肌纤维中MyHCI、MyHC2a、MyHC2b和MyHC2x4种MyHC的基因表达。结果表明，肌纤维类型的组成随培养时间的延长发生显著变化，从第4到12天，MyHC2b型肌纤维比例显著上升，而其余3种类型的肌纤维比例均显著下降。添加50μg·mL-1 CLA对肌纤维类型组成无显著影响。添加100μg·mL-1 CLA主要影响第12天的肌纤维类型组成，而添加150～200μg·mL-1 CLA则可显著改变第4～12天的肌纤维类型组成，即显著提高MyHCI和MyHC2a型肌纤维比例，显著降低MyHC2x和MyHC2b型肌纤维比例。以上结果提示，添加CLA可使肌纤维类型组成发生变化，且该作用与添加水平和处理时间密切相关。CLA对肌纤维类型组成的影响主要表现为提高MyHCI和MyHC2a型肌纤维比例，降低MyHC2b和MyHC2x型肌纤维比例，这在一定程度上可解释CLA提高猪肉品质的原因。This experiment was conducted to investigate the effect of CLA on the composition of myofiber types in skeletal muscle cells in vitro. The primary skeletal muscle satellite cells were used, and when the satellite cells were transformed into muscle cells, different CLA levels （0, 50, 100, 150, 200μg·mL-1） were added into the cells. After D4, D8 and D12 of culture, the ratios of mRNA abundance of four isoforms of myosin heavy chain （MyHC I, MyHC 2a, MyHC 2b and MyHC 2x） were determined by semi-quantitative RT-PCR. The results showed that the composition of myofiber types in skeletal muscle cells changed markedly with culture time. From D4 to D12, MyHC 2b type fiber was increased markedly, but the other three types of muscle fibers were decreased significantly. The addition of 50μg·mL-1 CLA had no effects on the composition of myofiber types. The effects of 100 μg·mL-1 CLA on the composition of myofiber types appeared mainly on D12, while 150-200 μg·mL-1 CLA affected significantly the composi- tion of myofiber types from D4 to D12, with an up-regulation of MyHC I and MyHC 2a type fibers, and a down-regulation of MyHC 2x and MyHC 2b type fibers. The results suggested that the composition of myofiber types in skeletal muscle cells was influenced by CLA, which depended on its dose and culture time. The effect of CLA on the composition of myofiber mainly was represented by increasing the proportions of MyHC I and MyHC 2a type fibers but decreasing the ratios of MyH 2b and MyHC 2x fibers, which could explain partially why CLA improved pork quality.

关 键 词：共轭亚油酸 肌卫星细胞 肌纤维类型 组成 猪 

分 类 号：S828[农业科学—畜牧学] S816[农业科学—畜牧兽医]