Cooper R G, Stokes M J, Edwards R H
University Department of Medicine, University of Liverpool, U.K.
J Neurol Sci. 1989 Oct;93(1):1-10. doi: 10.1016/0022-510x(89)90156-1.
Contractile properties of the adductor pollicis muscle were examined in 9 normal volunteers and 7 patients with histochemically proven myophosphorylase deficiency (McArdle's disease). Fatiguing contractions were produced by supramaximal stimulation of the ulnar nerve, delivered over a range of frequencies, to allow further examination of the mechanisms responsible for the premature fatigue in patients. The excessive reductions in force, demonstrated in patients at all frequencies, were not associated at high frequencies (50 and 100 Hz) with excessive declines in excitation (measured as compound muscle action potential). These results demonstrate that, in patients, myofibrillar activation failure occurs over and above that due to excitation failure. Abnormal slowing of relaxation mechanisms was also confirmed. These findings appear consistent with the hypothesis of inhibition of various ATPases by metabolic products. The observed, clear differences between normal subjects and myophosphorylase-deficient patients constitute the basis of an objective screening procedure for this and other glycolytic disorders.
对9名正常志愿者和7名经组织化学证实患有肌磷酸化酶缺乏症（麦克尔代尔病）的患者的拇收肌收缩特性进行了检查。通过在一系列频率下对尺神经进行超强刺激来产生疲劳性收缩，以便进一步研究导致患者过早疲劳的机制。在所有频率下患者所表现出的力量过度下降，在高频（50和100赫兹）时与兴奋过度下降（以复合肌肉动作电位衡量）无关。这些结果表明，在患者中，肌原纤维激活失败发生在由兴奋失败所导致的激活失败之上。松弛机制异常减慢也得到了证实。这些发现似乎与代谢产物抑制各种ATP酶的假说一致。正常受试者与肌磷酸化酶缺乏症患者之间观察到的明显差异构成了针对这种及其他糖酵解障碍进行客观筛查程序的基础。
