MECHANISMS OF SKELETAL MUSCLE FATIGUE

描述（改编自申请人摘要）：急性骨骼肌 活动经常导致疲劳的发展。疲劳的影响是 最常见于诸如运动竞技场、工作场所和 康复诊所在大多数情况下，骨骼肌疲劳导致 运动表现和工作效率下降。然而，在一些 在某些情况下，疲劳会增加患者对矫形手术的敏感性， 肌肉-肌腱损伤，并可能导致肌肉酸痛的发展。 尽管这些后果以及疲劳造成的个人和经济损失是 众所周知，冥想这种现象的机制并不完全 明白如果要开发预防和减轻疲劳和 它的最终结果，那么它是必要的，疲劳过程是充分的 明白拟议研究的总体目标是深入了解 骨骼肌疲劳的机制。疲劳似乎 是由兴奋收缩耦合过程的改变引起的 继发于肌浆网功能特性的变化 和收缩器之间的连通， 小管和SR。多年来，人们已经知道疲劳的发作是由 与肌糖原水平下降和积累有关 乳酸盐此外，其他糖酵解代谢产物在 肌肉纤维这表明碳水化合物代谢的某些方面 影响骨骼肌力量输出，可能是糖原消耗，或 代谢物的积累。因此，这一具体目标 建议如下。首先，为了确定糖原代谢物是否改变CA 和SR功能以及TT-SR通信。第二，确定如果 糖原提取，在体外，改变CA和SR功能以及TT-SR 通信第三，为了确定骨骼肌中的糖原消耗， 体内，改变CA和SR功能以及TT-SR通讯。的结果 拟议的实验将提供急需的信息， 调节骨骼肌疲劳的机制。此外，它还将试图 以确定肌糖原水平、CHO代谢和 疲劳过程

DESCRIPTION (Adapted from the applicant's abstract): Acute skeletal muscle activity often leads to the development of fatigue. The effects of fatigue are most often seen in venues such as the athletic arena, work site and rehabilitation clinic. In most instances, skeletal muscle fatigue results in decreased athletic performance and work productivity. However, in a number of cases, fatigue can increase ones susceptibility to orthopedic and musculo-tendinous injury and may lead to the development of muscle soreness. Although these consequences and the personal and financial costs of fatigue are well known, the mechanisms meditating this phenomenon are not completely understood. If means are to developed to prevent and alleviate both fatigue and its end results, then it is imperative that the fatigue process be fully understood. The overall objective of the proposed research is to gain insight into the mechanisms which mediate skeletal muscle fatigue. Fatigue appears to result from alterations in the excitation -contraction coupling process secondary to changes in the functional properties of the sarcoplasmic reticulum and the contractile apparatus or in the communication between the transverse tubule and SR. For years, it has been known that the onset of fatigue is associated with a reduction in the level of muscle glycogen and an accumulation of lactate. In addition, other glycolytic metabolites are elevated within the muscle fiber. This suggests that some aspect of carbohydrate metabolism influences skeletal muscle force output, possibly the depletion of glycogen or the accumulation of metabolites. Accordingly, the specific aims of this proposal are as follows. First, to determine if glycogen metabolites alter CA and SR function as well as TT-SR communication. Second, to determine if glycogen extraction, in vitro, alters CA and SR function as well as TT-SR communication. Third, to determine if glycogen depletion in skeletal muscle, in vivo, alters CA and SR function as well as TT-SR communication. The results of the proposed experiments will provide much needed information regarding the mechanisms which mediate skeletal muscle fatigue. In addition, it will attempt to identify direct links between muscle glycogen levels, CHO metabolism and the fatigue process.