T_3对大鼠心肌肌球蛋白重链基因表达调控作用的研究  

Regulative affect of 3, 3'5-triiodothyronine on the gene expression of cardiac myosin heavy chain in rats fed on grains from Keshan disease area

作　　者：李荣文[1] 朱筱娟[1] 李绍巍[1] 杨同书[1] 朱德志[1] 马丽[1] 肖淑芬[1] 

机构地区：[1]解放军农牧大学营养卫生教研室,白求恩医科大学地方病研究所,白求恩医科大学第一临床学院核医学科

出　　处：《中国地方病学杂志》1996年第6期326-329,共4页Chinese Jouranl of Endemiology

摘　　要：从克山病病区粮和非病区粮及常规饲料饲养的大鼠心肌中提取总ＲＮＡ，采用斑点印迹法分析其中的α和β－心肌肌球蛋白重链（ＣＭＩＩＣ）ｍＲＮＡ含量的变化并测定动物血清及心肌组织的Ｔ３、Ｔ４含量。结果表明，病区粮喂养大鼠心肌中α－ＣＭＨＣｍＲＮＡ含量降低，而β－ＣＭＨＣｍＲＮＡ含量升高；该组动物心肌和血清中Ｔ３含量显著下降，Ｔ４在血清中增加而在心肌中变化不大。向病区粮喂养大鼠腹腔注射Ｔ３（２μｇ／１００ｇ体重·ｄ，连续２次）观察大鼠心肌中ＣＭＨＣ基因表达及甲状腺激素水平的变化。给予外源Ｔ３后，动物心肌中α－ＣＭＨＣｍＲＮＡ明显上升，β－ＣＭＨＣ显著下降，提示在克山病病区粮饲养动物，Ｔ３对其心肌ＣＭＨＣ基因表达具有调控作用。The contents of a and β-cardiac myosin heavy chain(CMHC) mRNA in rate fed on grains from Keshan disease area (endemic grains,EG) were detected with the dot blot. The result showed that two months after treatment, α-CMHC mRNA level was significatly lower and β-CMHC mRNA level was significantly higher in myocardium of EG group as compared with those of non-EG group (P <0. 05).Meanwhile,the concentration of T3 in serum and myocardium of EG group decreased, but the concentration of T4 in serum increased. After treated with T3 for rats of EG group(2μg/100g body weight /daily twice by introperitoneal injection at the end of experiment),the α-CMHC mRNA content level remarkably.increased by 200% and the β-CMHC mRNA content level decreased by 30%than those of non-treated with T3 for EG group. It suggested that some pathogentic factors of Keshan disease may alter the expression of CMHC gene, and T3 maybe have a regulative effect on CMHC gene expression by inducing α-CMHC mRNA and represing β-CMllC mRNA.

关 键 词：心肌 肌球蛋白 基因表达 T3 T4 克山病 

分 类 号：R542.302[医药卫生—心血管疾病]