硒与大鼠甲状腺激素代谢的关系及其对心肌肌球蛋白重链基因表达的影响  

Relationship between Selenium and Metabolism of Thyroid Hormone and Its Effect on Expression of CMHC Gene in Rats

作　　者：李荣文[1] 李绍巍[2] 杨同书[2] 

机构地区：[1]解放军农牧大学畜牧水产系 [2]白求恩医科大学应用基础医学研究所

出　　处：《中国兽医学报》1996年第5期442-446,共5页Chinese Journal of Veterinary Science

摘　　要：应用心肌肌球蛋白重链（ＣＭＨＣ）基因探针分析了克山病病区粮（硒缺乏）和病区粮补硒喂养大鼠心肌中α和β－ＣＭＨＣ基因表达的变化，并观测了大鼠心肌Ｔ４５′－脱单碘酶活性和Ｔ３水平的改变。结果表明，日粮缺硒可导致大鼠ＣＭＨＣ基因表达的偏移，心肌Ｔ４５′－脱单碘酶活性下降和心肌Ｔ３水平的降低。病区粮补加硒后，上述改变明显向正常方向逆转。给病区粮喂养大鼠腹腔注射外源性Ｔ３，可使α－ＣＭＨＣｍＲＮＡ水平明显升高，而β－ＣＭＨＣｍＲＮＡ水平下降，表明Ｔ３对大鼠ＣＭＨＣ基因的表达具有一定的调控作用。The cDNA of α and β cardiac myosin heavy chain (CMHC) labelled with biotin was used as gene probes to detect α and β CMHC mRNA content in myocardium of rats fed with Keshan disease area grains (selenium deficiency), the activity of myocardial thyroxine 5′ monodeiodinase and concentration of T 3 and T 4 in myocardium and serum were investigated. The results showed that myocardial thyroxine 5′ monodeiodinase activities and T 3 level in myocardium were significantly reduced in rats fed with grains from endemic area, and the expression of CMHC gene was shifted. In addition, a reversible alteration was found after adding selenium. After treation of T 3 by intraperitoneal route for rats fed with endemic grains, the α CMHC mRNA level was remarkable increased and β CMHC mRNA level was decreased. It indicated that the expression of CMHC gene of rats was regulated by T 3 level in serum and myocardium. The effect of selenium on the expression of CMHC gene may be related to T 4 5′ monodeiodinase activity and T 3 level in myocardium.

关 键 词：硒 脱单碘酶 甲状腺激素 代谢 心肌肌球蛋白 

分 类 号：S816.72[农业科学—饲料科学] S852.2[农业科学—畜牧学]