Decreased Creatine Kinase Activity in Cultured Duchenne

Abstract ______________________________________________________________ Muscle cells were cultured from six patients with Duchenne muscular dystrophy and nine normal subjects. Protein and myosin content and pyruvate kinase (PK) activity were similar in normal and Duchenne muscular dystrophy cultures. Creatine kinase (CK) activity was lower in Duchenne muscular dystrophy cultures and the isoenzyme distribution indicated MB-CK was significantly lower, while BB-CK was significantly higher in later Duchenne muscular dystrophy cultures. This abnormal isoenzyme pattern suggested aberrant or impaired maturation of Duchenne muscular dystrophy myotubes in vitro. (J Child Neurol 1987; 2:17-21). Duchenne muscular dystrophy is a geneticdisease associated with relentless necrosis of muscle fibers. Although genetic defects are often studied in tissue culture, attempts to reproduce dys-trophic muscle in culture have been unsuccessful. ’ I In a previous paper,2 we described parameters of long-term growth and maturation for cultured nor-mal human skeletal muscle cells. We observed incom-plete maturation-lowered creatine kinase (CK