Linderholm H, Essén-Gustavsson B, Thornell L E
Department of Clinical Physiology, University of Umeå, Sweden.
J Intern Med. 1990 Jul;228(1):43-52. doi: 10.1111/j.1365-2796.1990.tb00191.x.
An unusual hereditary myopathy with paroxysmal myoglobinuria has been described previously. We have studied muscle biopsy specimens taken before and after exercise to exhaustion (24 min at 20-25 W) in a young woman with this condition. Marked glycogenolysis with lactate production and marked phosphagen breakdown (ATP + CP) were observed after exercise, and almost all type I fibres were found to be depleted of glycogen. Succinate dehydrogenase (SDH) activity was low, while the activities of 3-OH-acyl-CoA-dehydrogenase, phosphofructokinase, phosphorylase and lactate dehydrogenase were normal. On electron microscopy, the mitochondria showed abnormalities typical of mitochondrial myopathy. The findings in our patient suggest a limitation of mitochondrial function, probably related to SDH in the tricarboxylic acid cycle and complex II in the electron transport chain. This may explain the inability of ATP regeneration to keep pace with ATP utilization during exercise. Other metabolic defects may coexist.
此前曾描述过一种伴有阵发性肌红蛋白尿的罕见遗传性肌病。我们对一名患有这种疾病的年轻女性在运动至疲惫（20 - 25瓦，持续24分钟）前后所取的肌肉活检标本进行了研究。运动后观察到明显的糖原分解伴乳酸生成以及明显的磷酸原分解（ATP + CP），并且几乎所有I型纤维的糖原均被耗尽。琥珀酸脱氢酶（SDH）活性较低，而3 - 羟基酰基辅酶A脱氢酶、磷酸果糖激酶、磷酸化酶和乳酸脱氢酶的活性正常。在电子显微镜下，线粒体显示出线粒体肌病的典型异常。我们患者的这些发现提示线粒体功能存在局限性，可能与三羧酸循环中的SDH以及电子传递链中的复合物II有关。这可能解释了运动期间ATP再生无法跟上ATP利用的情况。可能还存在其他共存的情况。
