《中国康复理论与实践》

《中国康复理论与实践》 ›› 2006, Vol. 12 ›› Issue (04): 298-300.

• 基础研究 • 上一篇    下一篇

大鼠脊髓横断早期比目鱼肌重量与肌球蛋白重链亚型mRNA表达的变化

范晓华1,2,3; 纪树荣1,2; 周红俊1.2   

  1. 1.首都医科大学康复医学院 北京市 100068;2.北京博爱医院 北京市 100068;3.山东省立医院 山东济南市 250021
  • 收稿日期:2006-02-14 出版日期:2006-04-25 发布日期:2006-04-25

Changes of the Soleus Muscle Mass and Expression of Myosin Heavy Chain Isoforms mRNA after Acute Spinal Cord Transection

FAN Xiao-hua, JI Shu-rong, ZHOU Hong-jun   

  1. Faculty of Rehabilitation Medicine of Capital University of Medical Sciences, Beijing 100068, China
  • Received:2006-02-14 Published:2006-04-25 Online:2006-04-25

PDF (PC)

被引次数

5

摘要： 目的观察大鼠脊髓横断后早期比目鱼肌重量及肌球蛋白重链(MHC)各亚型mRNA表达的变化规律。方法40只雌性Wistar大鼠随机分为对照组(10只)与脊髓横断7d组(ST7)、15d组(ST15)、30d组(ST30),各10只,脊髓横断水平T8～T10。分别于横断后7、15、30d取后肢比目鱼肌称重,采用半定量RT-PCR方法观察MHC各亚型mRNA表达的变化。结果脊髓横断各组比目鱼肌重量均较对照组下降(P<0.05)。ST15、ST30组比目鱼肌绝对与相对重量均较ST7组下降(P<0.05)。对照组比目鱼肌只表达MHC-I与MHC-IIa,脊髓横断各组在横断7d后出现MHC-IIx与MHC-IIb的表达,横断后各时间点MHC-I mRNA的表达持续下调;MHC-IIa与MHC-IIxmRNA的表达持续上调;MHC-IIb mRNA的表达维持在低水平。结论脊髓横断主要在早期影响肌肉的重量;脊髓横断后MHC的表达发生由慢型向快型的转化,MHC随神经肌肉活动的减少表现出可塑性。

关键词: 脊髓横断, 比目鱼肌, 肌肉重量, 肌球蛋白重链, 逆转录聚合酶链式反应

Abstract: ObjectiveTo investigate the rule of changes of the soleus mass and expression of myosin heavy chain (MHC) isoforms mRNA.Methods40 female Wistar rats were divided randomly into the control group and three spinal cord transection (ST) groups, ST7, ST15, and ST30 with 10 animals in each group. Rats in ST groups were subjected to a complete ST between T8 and T10 levels. The right soleus was dissected and weighed at 7, 15, 30 days after ST, and the expression of MHC mRNA isoforms was measured by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR).ResultsThe Absolute and relative soleus masses in three ST groups were lower significantly than those of control group (P<0.05). The soleus mass in ST15 and ST30 groups were lower than that of ST7 group (P<0.05). The soleus of control group predominantly expressed MHC-I and some MHC-IIa, whereas the soleus began to express MHC-IIx and MHC-IIb after ST, except for MHC-I and MHC-IIa. ST induced consistently down-regulation of MHC-I mRNA and up-regulation of MHC-IIx and MHC-IIa at three time points after ST. The level of MHC-IIb mRNA expression was very low at three time points after ST.ConclusionST can influence the soleus mass at early stage after ST. ST induces a shift toward a faster muscle phenotype from slow to fast MHC isoform. MHC demonstrates plasticity in response to decrease neuromuscular activation.

Key words: spinal cord transection, soleus, muscle mass, myosin heavy chain, reverse transcriptase polymerase chain reaction (RT-PCR)