摘要
目的:探讨低频电刺激对低氧高二氧化碳模型大鼠比目鱼肌肌纤维类型转变的影响。方法:成年SD大鼠40只随机分成4组:正常组10只,捆绑组10只,造模组10只,低频电刺激组10只。造模组、捆绑组及低频电刺激组大鼠置于低氧高二氧化碳舱内造模,每次持续8 h,总共4周。低频电刺激组在持续造模2周后,用电刺激仪对大鼠进行30 min,30 Hz,1:1循环模式的低频电刺激,低频电刺激维持2周;捆绑组仅做捆绑及贴电极片处理。HE染色检测大鼠比目鱼肌病理改变,免疫组织化学观察比目鱼肌肌纤维类型转变,qRT-PCR检测MHC-I、MHC-Ia/Ix mRNA水平,Western Blot检测比目鱼肌MHC-I、雌激素相关受体γ(ERRγ)、过氧化物酶体增殖物受体β(PPARβ)蛋白含量的变化。结果:相比正常组,捆绑组及造模组大鼠比目鱼肌局部炎症反应明显,肌纤维横截面积明显下降,MHC-I以及PPARβ蛋白含量明显下降,MHC-I mRNA下降,MHCIa/Ix mRNA含量升高。相比捆绑组或造模组,低频电刺激组大鼠比目鱼肌局部炎症反应减轻,MHC-I、ERRγ及PPARβ蛋白含量明显增加,MHC-I mRNA含量明显升高,MHC-Ia/Ix mRNA明显下降。结论:低氧高二氧化碳可致大鼠比目鱼肌MHC-I向MHC-Ia/Ix型纤维转变,而低频电刺激可部分逆转低氧高二氧化碳所致的肌纤维类型转变。PPARβ、ERRγ蛋白可能参与其中调节。
Objective： To explore the effect of low frequency electrical stimulation on transition of rats＇ soleus muscle fibre type after the long term chronic hypoxia-hypercapnia exposure. Methods： Forty male Sprague Dawley rats were randomly divided into four groups： the Normal Control（NC）, Hypoxia-hypercapnia（HH）, Hypoxia-hypercapnia＋Tie-up（HT） and Low-frequency electrical stimulation（LFES）. The HH, HT and LFES were placed in a chamber with hypoxia-hypercapnia for 8 h/d, 4 weeks in all. After 2 weeks, 30 min, 30 Hz, 1：1 cycle electrical stimulation was applied in the LEFS, this procedure lasted 2 weeks. The HT were only tied up and placed with electrode plates. Hematoxylin and Eeosin staining was used to observe pathological change of soleus muscle. Soleus fiber composition was visualized with immunochemistry, q RT-PCR was used to detect mRNA levels of MHC-I, MHC-Ⅱa and Ⅱx. Proteins expression of MHC-I, ERRγ, PPARβ was tested by Western Blot. Results： Increased inflammation cells and MHC-Ⅱa/Ⅱx mRNA, decreased cross section area, MHC-I, PPAR β protein and MHC-I mRNA were found in the HH and HT group compared with the NC. Compared with the HH and HT respectively, inflammation cells and MHC-Ⅱa/Ⅱx mRNA level were decreased, while mRNA level of MHC-I and protein expression of MHC-I, ERRγ and PPARβ were significantly increased after LFES. Conclusion： Hypoxia-hypercapnia leads to soleus muscle transition of MHC-I into MHC-Ⅱa/Ⅱx. However, LFES may reverse the muscle fiber transition induced by HH. PPARβ and ERRγ may have participates in this process.
出处
《温州医科大学学报》
CAS
2016年第3期157-162,共6页
Journal of Wenzhou Medical University
基金
浙江省自然科学基金资助项目(Y2080503)
