Sperl 1994 J Inher Metab Dis
|Sperl W, Skladal D, Lanznaster N, Schranzhofer R, Zaunschirm G, Gnaiger E, Gellerich FN (1994) Polarographic studies of saponin-skinned muscle fibers in patients with mitochondrial myopathies. J Inher Metab Dis 17:307-10.|
Abstract: A large number of enzyme systems are examined for the diagnosis of mitochondrial myopathies including the pyruvate dehidrogenase complex, tricarboxylic-acid-cycle enzymes and respiratory chain complexes. This investigation can be carried out in frozen tissue. For the study of oxidative phosphorilation in intact mitochondria, fresh muscle tissue is required, and isolation of mitochondria from large amounts of tissue (at least 500-1000 mg) is necessary. For ethical reason this imposes a serious limitation, especially in paediatric patients. Radiochemical measurements of oxidation rates in various substrates in 600 g supernatant from 100-300 mg amounts of muscle tissue has partly overcome this problem. (Bookelman et.al., 1978). Owing to the low yield, the danger of selective isolation of different mitochondrial populations exists. In addition, since isolated mitochondria removed from their natural environment are more or less unstable, there is a possibility of artefacts. Recently, investigation of saponin-skinned muscle fibers by polarographic methods was reported for cardiac (Veksler et. al., 1987) and human muscle tissue. In such permeabilized fibers, study of mitochondrial respiratory control is possible as in isolated mitochondria but without the disadvantages mentioned above (Letellier et.al., 1992; Kunz et.al., 1993). We investigated saponin-skinned muscle fibers in three patients suspected of a mitochondrial encephalo-myopathy. For our studies we used a specially developed respirometer with a sensitivity ten times higher than the established instruments (Kunz et.al., 1993).
Labels: MiParea: Respiration, mt-Medicine, Patients Pathology: Inherited
Organism: Human Tissue;cell: Skeletal muscle Preparation: Permeabilized tissue
Coupling state: LEAK, OXPHOS Pathway: N, S, CIV HRR: Oxygraph-2k