不同强度运动训练对大鼠比目鱼肌肌纤维类型与MHC亚型的影响

Effects of Different Intensity Exercise on the Rat's SOL Muscle Fiber Type and MHC Hypotype

目的:检测不同强度运动训练后成年SD大鼠比目鱼肌中不同肌纤维类型以及MHC亚型,旨在探讨不同强度运动训练引起比目鱼肌肌纤维和MHC亚型之间相互转化。方法:健康SD大鼠40只,随机分成安静组、小强度运动组、中等强度运动组和大强度运动组。取大鼠右侧后肢比目鱼肌,分别用ATP酶染色法鉴定I型和II型肌纤维;SDS-PAGE凝胶电泳技术分离MHCI、MHCIIa、MHCIIb和MHCIIx。结果:1)小强度运动使比目鱼肌I型肌纤维的面密度增加(P<0.01),II型肌纤维的面密度减少(P<0.05)。2)中等强度运动使I型肌纤维的面密度减少,II型肌纤维的面密度增加(P<0.05)。3)小强度运动使肌纤维MHCI%升高,MHCIIb%降低(P<0.01);中等强度运动使肌纤维MHCI%和MHCIIb%降低,MHCIIa%升高(P<0.01);大强度运动使肌纤维MHCIIx%升高(P<0.01)。结论:不同强度运动可以引起比目鱼肌MHC亚型之间发生变化,小强度运动引起MHCIIb向MHCIIx、MHCIIa、MHCI方向变化;中等强度、大强度运动引起MHCI、MHCIIb向MHCIIx、MHCIIa变化。

Object： The objective of this study was to investigate the percentage of all kinds of muscle fibers change situation on SOL in SD rats to different intensity exercise in hope of finding whether exercise leads muscle fiber and MHC transforming.Method： 40 male adult Sprague-Dawley rats were randomly divided into four groups： control（C,n=10）,light exercise（LE,n=10）,moderate exercise（ME,n=10） and high exercise（HE,m=10）.The right side of rats hind legs soleus muscle was taken.The type I muscle fibers and type II muscle fibers were distinguished through ATPase coloration and isoforms of MHC were separated into MHCI,MHC II a,MHC II b and MHC II x through SDS-PAGE electrophoresis.Results：1）The I muscle type＇s superficial density increased（P0.01）,the II muscle type＇s superficial density reduced by low exercise（P0.05）.2）After medium intensity exercise,the I muscle type＇s superficial density reduced,the II muscle type＇s superficial density increased（P0.05）.3）Compares with C group,the muscle type＇s MHCI% increased,the muscle type＇s MHCIIb% reduced afer low intensity exercise（P0.01）.After medium intensity exercise,the muscle type＇s MHCIIb% and MHCI% reduced,the muscle type＇s MHCIIa% increased（P0.01）.Through high intensity exercise,the muscle type＇s MHCIIx% increased in Soleus（P0.01）.Conclusion： different exercise intensity can cause Soleus muscle MHC subtype change.Low intensity exercise MHCIIb caused the change to MHCIIx,MHCIIa,MHCI.Medium strength and high intensity exercise caused muscle type transformation from MHCI and MHCIIb to MHCIIx and MHCIIa.