Concentrations of K and Na in Skeletal Muscle of Mice With a Hereditary Myopathy (Dystrophia Muscularis)

Abstract

Exchangeable body potassium (K_e), muscle potassium and muscle sodium concentrations have been measured in hereditarily dystrophic mice and in their normal littermates. Both K_e and K³⁹/gm muscle were depressed in the dystrophics approximately 20% below the mean normal value; however, the concentration of Na²³/gm muscle was higher by 50%, on the average, in the dystrophic tissue. The data suggest a partial replacement of intracellular by extracellular space in the dystrophic mice. Thus, this form of hereditary muscular dystrophy is qualitatively similar, with regard to K and Na concentrations, to human muscular dystrophy, vitamin E deficiency in rabbits, nutritional dystrophy in calves, and denervation in puppies.