EFFECTS OF EXERSICE STIMULATION ON RECOVERY FROM INJURED MUSCLE

生理学证据表明，电收缩引起的收缩功能障碍包括由于结构和形态的破坏而导致的肌肉损伤，本研究旨在探讨各种刺激因素对损伤肌肉再生的影响。为研究大鼠指(趾)长肌退变再生的形态学变化过程，采用周期性偏心收缩、下坡跑和注射布比卡因的方法，1)偏心收缩试验后3~5天可见大量肌纤维受损。下坡后3天，间接刺激引起的强直性张力小于直接刺激引起的张力，部分神经肌肉接头出现不融合的运动性轴突。电子显微镜观察提示，神经肌肉接头的再生依赖于突触膜系统的重塑。2)老年肌肉超负荷易损伤肌肉主体，恢复速度慢，提示应避免超负荷随衰老进程而运动。3)主动轮式训练引起的肌肉损伤与下坡训练一致，影响了肌纤维类型的转变。4)去训练后肌纤维转化增加，布比卡因诱导的损伤和再生可能在神经肌肉接头损伤的神经转化过程中起作用。5)肌纤维横截面积扩大分布，涉及的纤维很小，尤其是IIB型纤维损伤后的恢复。

Physiological evidences suggests that contractile faillure from eccecntric contraction included muscle injury because structurral and motphorogical disruption.The pufpbse of this study was to examine the effect of various stimulations bn injured muscle regeneration. To study the process of morphorgical changes associated with degeneration and regeneration in piantaiis or extesor digitrum iongus muscle of rat, cyclic eccentric contraction, dowm -hill running or bupivacaine injection was induced.1) Significant number of damaged muscle fibers were found 3-5 days after eccentric contraction test. Three days after downhill running the tetanic tension by indirected stimulation was less than direct stimulate tension; and some neuromuscular junctions showed unfusimotor axons. The electron Microscopic observations suggest that the neuromuscular junctions regeneration depends on the remodeling of Synaptic membrane systems.2) The muscle main body was damaged easily by the overload in old muscle, and recovery speeds was slow, it suggested that especially the movement of the overload with aging progress should be avoided, an enough rest is needed when muscle was damaged.3) The voluntarily wheel running training caused a muscle damage consistent with the case of down-hill running in rat hindimb muscle and affected the transformation of muscle fiber types.4)increament of muscle fiber transformation occurred after detraining and bupivacaine induced injury and regeneration may have a role in the nerve conversion of the neuromuscular junction injury process.5 )Extensiye distribution of muscle fiber cross-sectional area, involved very small fiber observed, particularly in type Iib fiber recovery after injuy.