废用状态下大鼠骨骼肌再负荷对比目鱼肌calpain活性和肌细胞膜通透性的影响  

Effects of disuse and reloading on calpain activity and cell membrane permeability of soleus muscle fibers in rats

作　　者：何越[1] 高云芳[1] 张少颖[1] 张扬媚[1] 孙小勇[1] 王慧平[1] 

机构地区：[1]西北大学生命科学学院,陕西西安710069

出　　处：《中国病理生理杂志》2012年第8期1500-1503,共4页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.30770273);2011年度高等学校博士学科点专项科研基金资助课题(No.20116101110013);陕西省教育厅省级重点实验室重点科研计划项目(No.11JS092)

摘　　要：目的:探讨废用状态及废用后再负荷对大鼠比目鱼肌钙蛋白酶(calpain)活性和肌细胞膜通透性的影响。方法:采用尾部悬吊法建立大鼠后肢骨骼肌废用模型,将48只雌性SD大鼠分为正常组(CON)、正常运动组(CON+T)、吊尾2周组(TS)和吊尾2周后运动组(TS+T),每组12只。用伊文思蓝(Evans blue,EB)作为示踪物,检测细胞膜的通透性;用酪蛋白酶谱法检测calpain的活性。结果:CON组和CON+T组细胞间隙充满EB,肌细胞内则未见,TS组极少量肌细胞有EB进入,TS+T组有部分细胞内充盈EB。TS组calpain水解条带与正常组相比吸光度呈增加趋势,并且有自激发条带出现,TS+T组calpain水解条带更加明显,calpian水解活性明显增强。结论:大鼠在经历2周吊尾后的再负荷,肌细胞膜通透性升高,屏障功能受损,可能与calpain水解肌细胞膜上的骨架蛋白有关;由calpian介导的细胞骨架蛋白的降解加速可能是导致废用后再负荷骨骼肌损伤的重要机制。To investigate the effects of disuse and reloading on the calpain activity and cell membrane permeability of soleus muscle fibers in rats. METHODS ： Tail - suspension （TS） rats were used as a muscular atrophy model. The female rats were randomly divided into control group （CON）, control group with training （CON ＋ T）, 2 - week TS group （TS） and 2 -week TS with training group （TS ＋T）. The changes of cell membrane permeability and cal- pain activity were detected with Evans blue （EB） as a tracer and casein zymography, respectively. RESULTS： The re- sults showed that the EB was full of intercellular space in soleus muscle fibers in CON group, a few in TS group and much more in TS ＋ T group, respectively. In TS group and TS ＋ T group, some self - excitation bands appeared and absorbance of calpain hydrolysis bands was significantly increased compared with those in the controls. CONCLUSION： The results suggest that the cell membrane permeability in TS ＋ T group raises and the membrane barrier function is damaged. This may attribute to the hydrolysis of membrane skeleton proteins by calpain. Calpain - mediated accelerated degradation of cy- toskeleton proteins may be an important mechanism of skeletal muscle injury- induced by reloading.

关 键 词：萎缩 废用性 伊文思蓝 细胞膜通透性 钙蛋白酶 肌损伤 

分 类 号：Q445[生物学—生理学]