摘要
目的:观察大鼠脑缺血再灌注损伤后患侧骨骼肌早期形态学变化及肌萎缩素1(atrogin-1)和肌环指蛋白1(MuRF-1)mRNA表达水平的变化。方法:60只雄性Wistar大鼠,10只为假手术对照组(A组),其余50只采用Longa线栓法建立大鼠左侧大脑中动脉栓塞(MCAO)模型,其中30只造模成功大鼠随机分为B、C、D组,每组10只。B组为造模成功后1d组,C组为造模成功后4d组,D组为造模成功后7d组。应用Bederson评分评价大鼠的神经损伤后的恢复情况;分别获取A、B、C、D四组右侧肱二头肌,对各组通过HE染色检测肌纤维横截面积;通过荧光定量RT-PCR观察大鼠患侧骨骼肌中atrogin-1和MuRF-1 mRNA表达的变化。结果:B、C、D组大鼠Bederson评分明显高于对照组A组(P<0.05);B、C、D组大鼠间Bederson评分差异无显著性(P>0.05)。患侧骨骼肌HE染色显示A、B、C组肌纤维横截面积两两比较,差异无显著性意义(P>0.05);D组大鼠患侧骨骼肌肌纤维横截面积分别与其余3组相比,差异均有显著性意义(P<0.05)。B、C、D组大鼠患侧atrogin-1和MuRF-1 mRNA的表达水平分别与对照组相比,差异均有显著性意义(P<0.05);B组与C组相比较差异无显著(P>0.05);D组大鼠分别与B、C组相比,差异均有显著性意义(P<0.05)。结论:脑缺血再灌注损伤大鼠早期患侧骨骼肌形态学即发生变化,其机制可能与Atrogin-1和MuRF-1 mRNA在骨骼肌中高表达,泛素连接酶蛋白降解通路被激活有关。
To study the early histomorphological changes and levels of atrogin-1 and MuRF-1 mRNA in skele- tral muscle of paralytic limb in cerebral ischemiaJreperfusion injury rat＇s model. Method： Sixty male Wistar rats were prepared, of which 10 for the sham operation group （A）, and the remain- ing 50 for establishing model with Longa suture method on left side using middle cerebral artery occlusion （MCAO）. Thirty successful model rats were randomly divided into B, C and D groups, each 10 rats. Rats of groups B, C and D were taken at 1 day, 4 days and 7 days after successful modeling respectively. Bederson score was used for evaluation of rats recovery after nerve injury. Right biceps brachii muscles of four groups were sectioned off for histomorphologic examination. The cross-sectional area of muscle fibers were compared with HE staining. Fluorescence quantitative RT-PCR was used to observe changes of skeletal muscle atrogin-1 and MuRF-1 mRNA expression.Result： Bederson scores of B, C and D groups were significantly higher compared with that of group A （P〈 0.05）; there was no significant difference among B, C and D groups （/9〉0.05）. Paralyzed muscles HE staining showed： muscle fiber cross-sectional area of A, B and C groups were compared in pairs, the differences were not statistically significant （P〉0.05）. The muscle fiber cross-sectional area of D group was compared with that of the other three groups, the differences were statistically significant （/~〈0.05）. Atrogin-1 and MuRF-1 mRNA expression levels of B, C and D groups were compared with control group, the differences were statistically significant （P〈0.05）; there was no significant difference between B group and C group（P〉0.05）; but when D group was compared with B and C group respectively, the differences were statistically significant （P〈0.05）. Conclusion： In cerebral ischemia-reperfusion injury in rat＇s early paralyzed skeletal muscles, appeared morpho- logical changes, it＇s mechanism may be related to atrogin-1 and MuRF-1 mRNA high expression in rats＇ skele- tal muscle and ubiquitin ligase pathway of protein degradation was activated.
出处
《中国康复医学杂志》
CAS
CSCD
北大核心
2014年第7期610-614,共5页
Chinese Journal of Rehabilitation Medicine
