The influence of sustained magnesium deficiency on muscle potassium repletion.

Abstract

Abstract The changes in electrolyte composition effected in serum and muscle by simultaneous repletion of K and Mg were contrasted to those changes occurring following K repletion alone in rats initially made deficient in both Mg and K. It is concluded that: (1) Sustained Mg deficiency can impair repletion of muscle K. (2) The azotemia accompanying Mg and K deficiency is entirely reversible by restoration of both K and Mg, but not by K repletion alone. This change may be ascribable in part to an amelioration of the intensity of nephrocalcinosis in the doubly repleted group. (3) There is no increase in mortality rate associated with K repletion alone as contrasted to K and Mg replacement in rats initially depleted of both cations. (4) There is an apparent dissimilarity in the rate of muscle depletion of the principal intracellular cations, a deficit of K being more readily achieved than for Mg.