A method for quantitative measurement of mitochondrial creatine kinase in human skeletal muscle

Abstract

Defects in the mitochondrial energy generating system in patients with a mitochondrial myopathy are known to be localized in various enzyme complexes involved in energy production. Such a defect may exist at the level of mitochondrial creatine kinase (Mi-CK). On that account we have developed a method for measurement of the enzyme activity in human skeletal muscle biopsy material (>10mg). Interfering creatine kinase isoenzymes are removed by anion exchange and affinity chromatography. The activity of Mi-CK in reference skeletal muscle homogenates amounts to 240 ± 88 mU/mg protein (30 ± 8.0 mU/mg wet weight).