Protein synthesis in muscle cultures from patients with Duchenne muscular dystrophy. Calcium and A23187 ionophore dependent changes.

Muscle samples for cultures were obtained from the quadriceps by open biopsy under local anesthesia in five patients with early stage of Duchenne muscular dystrophy (DMD) and 10 controls. Primary cultures were grown in Eagle's Minimum Essential Medium (MEM) with 20 per cent fetal calf serum. After 4 weeks, cells were trypsinized, counted, subcultured for 5 days in MEM with 5 per cent horse serum and finally incubated for 4 h with (3H) leucine. Ttal protein synthesis showed a significant decrease (half of control values) only in muscle cultures from patients with DMD. Addition of calclium chloride alone or with A23187 ionophore normalized this defect in protein synthesis. By contrast, myosin heavy chain synthesis was measured and found normal in all paitents.