Land J M, Morgan-Hughes J A, Clark J B
J Neurol Sci. 1981 Apr;50(1):1-13. doi: 10.1016/0022-510x(81)90038-1.
This paper presents biochemical data upon a young male with a mitochondrial myopathy characterised by weakness, severe exercise intolerance, muscle wasting and exercise-induced lactic acidaemia. Two similar cases have been previously documented (Morgan-Hughes et al. 1979). This report more precisely locates the mitochondrial defect. In vitro mitochondrial studies show markedly decreased respiratory rates with all NAD-linked substrates whilst that with flavin-linked succinate is normal. Oxidative phosphorylation is normally coupled. Mitochondrial cytochrome components as determined by low temperature spectroscopy are normal. NADH-ferricyanide reductase and primary dehydrogenase activities are present at levels far in excess of that required to support normal NAD-linked substrate oxidation rates. Intramitochondrial NAD levels are similar to those found in other mammalian muscle. It is proposed therefore that the mitochondrial defect is situated between NADH dehydrogenase and the CoQ--Cytochrome b complex; possibly being a derangement of a non-haem iron sulphur centre.
本文呈现了一名患有线粒体肌病的年轻男性的生化数据，该疾病的特征为肌无力、严重运动不耐受、肌肉萎缩以及运动诱发的乳酸性血症。此前已有两例类似病例的记录（摩根 - 休斯等人，1979年）。本报告更精确地定位了线粒体缺陷。体外线粒体研究表明，所有与NAD相关的底物的呼吸速率均显著降低，而与黄素相关的琥珀酸的呼吸速率正常。氧化磷酸化正常偶联。通过低温光谱法测定的线粒体细胞色素成分正常。NADH - 铁氰化物还原酶和初级脱氢酶的活性水平远远超过支持正常NAD相关底物氧化速率所需的水平。线粒体内的NAD水平与其他哺乳动物肌肉中的水平相似。因此，有人提出线粒体缺陷位于NADH脱氢酶和辅酶Q - 细胞色素b复合体之间；可能是一种非血红素铁硫中心的紊乱。
