Muscular Dystrophy. Potassium Exchange in Residual Muscle

Abstract

Two methods are given. One serves to estimate the amount of K exchanged in the whole human body over a period of time, the other measures the rate of K turnover in human muscle. Principally the 2 methods utilize similar principles but differ from the isotope dilution principle commonly used to eliminate exchangeable substances in the whole body. The first of these methods demonstrated that the dystrophy patients turned over less K in the whole body than did control subjects. This difference is explained by the smaller muscle mass of the patients and also by the decreased K concentration in the residual muscle. Rate of turnover as measured directly upon the muscle was found to be in the same range in both patients and control subjects. The observed low K concentration of the fiber water is not an etiological factor in dystrophy.