Creatine kinase isoenzymes in cultured human muscle cells. I. Comparison of Duchenne muscular dystrophy with other myopathic and neurogenic disease.

The amounts of creatine kinase (CK) and the proportions of isoenzymes have been investigated in human primary cultures. There were increases in total CK activity and the transitions in the isoenzyme profiles showed initial patterns in which only the brain form is present, and later in culture showed patterns in which the muscle or hybrid forms are also present. These changes are similar to those found in muscle cultures grown from other species. These parameters have been compared in cultures derived from boys with Duchenne muscular dystrophy and from patients with various neurological diseases. The dystrophic CK activities were significantly lower and the amounts of brain-type isoenzyme were significantly higher than in the cultures from patients with neurogenic disorders, but the values were similar to the cultures from the myopathic group of diseases. The dystrophic CK isoenzyme profiles resembled those produced by cultures examined at time points, early in their growth period when they were less differentiated.