Yokoi F, Hara T, Iio M, Nonaka I, Satoyoshi E
National Center of Neurology and Psychiatry, Tokyo, Japan.
J Neurol Sci. 1990 Nov;99(2-3):339-48. doi: 10.1016/0022-510x(90)90168-m.
We examined pyruvate turnover using 1-[11C]pyruvate in the brain and epicranial muscle of 6 patients with mitochondrial encephalomyopathy (MEM), diagnosed by muscle biopsy and mitochondrial enzyme assay. The radioactivity was measured by positron emission tomography (PET). The time-activity curve for 11C in both brain and muscle generated after i.v. injection of 1-[11C]pyruvate consisted of 2 components in normal subjects and patients, i.e. a fast and a slow component which were assumed to represent the aerobic (mitochondrial) and anaerobic (glycolytic) metabolism of pyruvate, respectively. In the brain and muscle of patients, the aerobic component was smaller and the anaerobic larger than in normals. The extent of this abnormality seemed to reflect the severity of the disease. The same slight abnormality for [11C]pyruvate turnover was also observed in the brain of MEM patients who were without cerebral symptoms. Cerebral blood flow (CBF) and cerebral oxygen consumption (CMRO2) of most patients were lower than those of normals, and the oxygen extraction fraction (OEF) was decreased in many patients.
我们使用1-[¹¹C]丙酮酸对6例经肌肉活检和线粒体酶测定确诊的线粒体脑肌病（MEM）患者的大脑和头顶部肌肉中的丙酮酸周转率进行了检测。通过正电子发射断层扫描（PET）测量放射性。静脉注射1-[¹¹C]丙酮酸后，正常受试者和患者大脑及肌肉中¹¹C的时间-活性曲线均由两个成分组成，即快成分和慢成分，分别被认为代表丙酮酸的有氧（线粒体）代谢和无氧（糖酵解）代谢。与正常情况相比，患者大脑和肌肉中的有氧成分较小，无氧成分较大。这种异常程度似乎反映了疾病的严重程度。在没有脑部症状的MEM患者大脑中也观察到了[¹¹C]丙酮酸周转率相同的轻微异常。大多数患者的脑血流量（CBF）和脑氧耗量（CMRO₂）低于正常水平，许多患者的氧摄取分数（OEF）降低。
