Kemp G J, Taylor D J, Barnes P R, Wilson J, Radda G K
MRC Biochemical and Clinical Magnetic Resonance Unit, Oxford Radcliffe Hospital NHS Trust, United Kingdom.
Ann Neurol. 1995 Oct;38(4):681-4. doi: 10.1002/ana.410380421.
Alternating hemiplegia of childhood is an uncommon disease characterized by repeated, transient attacks of hemiplegia. Its pathophysiology is uncertain, but attention recently has focused on possible mitochondrial abnormalities. Using 31P magnetic resonance spectroscopy, we studied gastrocnemius muscle in 5 patients with alternating hemiplegia, aged 8 to 30 (mean, 18) years, at rest and during incremental aerobic exercise and recovery. There were no significant differences in resting muscle between patients and a control group aged 7 to 42 (mean, 19) years. Exercise performance was grossly impaired in the patients, the mean duration being 30% of normal. The total change in pH during exercise was somewhat less than in control subjects, while the changes in phosphocreatine concentration and intracellular ADP were similar. Thus the average overall rate of fall of phosphocreatine concentration during exercise was three-fold greater than in control subjects. However, the initial rate of ATP turnover at the start of exercise (a measure of muscle mass and efficiency) was not abnormal. During recovery, both the initial rate of phosphocreatine resynthesis and the calculated mitochondrial capacity were reduced by about 35%. This mitochondrial defect probably explains most of the abnormalities seen during exercise.
儿童交替性偏瘫是一种罕见疾病，其特征为反复出现的短暂性偏瘫发作。其病理生理学尚不确定，但最近注意力集中在可能的线粒体异常上。我们使用31P磁共振波谱法，对5例年龄在8至30岁（平均18岁）的交替性偏瘫患者的腓肠肌进行了研究，观察其在静息状态、递增有氧运动及恢复过程中的情况。患者静息肌肉与年龄在7至42岁（平均19岁）的对照组之间无显著差异。患者的运动能力严重受损，平均持续时间为正常的30%。运动期间pH值的总变化略小于对照组，而磷酸肌酸浓度和细胞内ADP的变化相似。因此，运动期间磷酸肌酸浓度的平均总体下降速率比对照组大三倍。然而，运动开始时ATP周转的初始速率（衡量肌肉质量和效率的指标）并无异常。在恢复过程中，磷酸肌酸再合成的初始速率和计算得出的线粒体容量均降低了约35%。这种线粒体缺陷可能解释了运动期间出现的大多数异常情况。
