模拟运动负荷电刺激对蟾蜍骨骼肌肌球蛋白分解代谢影响的免疫印迹观察

Immunoblotting Observation on Changes of Myosin Degradation Metabolism in Toad Gastrocnemius Muscle Electric Stmulation under Simulated Exercise Load.

目的探讨运动员体育训练中运动负荷的合理安排。方法通过ＳＤＳＰＡＧＥ垂直板电泳和和免疫印迹方法观察不同强度电刺激后蟾蜍腓肠肌肌球蛋白变化情况。结果（１）大强度电刺激后蟾蜍腓肠肌蛋白分解加强。（２）两次大强度电刺激后，出现分子量分别为４３ＫＤ、３８ＫＤ的肌球蛋白降解片段。（３） 大强度电刺激后施加小强度电刺激，已出现的分子量为４３ＫＤ的肌球蛋白降解片段消失。结论在体育训练中，连续大强度负荷会引起骨骼肌收缩蛋白的进一步降解，而大强度负荷后施加小强度负荷有利于其收缩蛋白结构和功能的恢复。

Objective To probe into the optimum exercise load in sports training. Method Myosin heavy chain degradation fragments produced by different intensity electric stimulation were identified in toad gastrocnemius muscle. The fragments were identified by electrophoresis of unfractionated extracts of toad gastrocnemius muscle on sodium dodecyl sulfate/polyacrylamide gels followed by immunoblotting on nitrocellulose sheets. Polyclonal antibody directed against the entire myosin were used to characterize the fragments. Result Toad gastrocnemius muscle protein degradation increased under high intensity electric stimulation;two kinds of Myosin degradation fragments whose molecular weight were 43KD、38KD respectively were produced by double high intensity electric stimulation; the molecular weight 43KD immunoreactive myosin fragments produced by high intensity electric stimulation disappeared under low intensity electric stimulation. Conclusion Continuous high intensity exercise load would make muscle contractile protein further degradate while low intensity exercise load would enhance the recover of contraction and function of the muscle.