THE DISTRIBUTION OF SODIUM AND POTASSIUM IN MAN 1

Abstract

Intracellular K and Na were calculated from simultaneous studies of body water distr. (total body water and extracellular fluid) and total body electrolyte as measured by the isotope dilution technic. The concn. of intracellular electrolyte was calculated per unit of intracellular water, per unit of cellular mass and per unit of body solid. Intracellular K avgd. 112 meq./l. (range 96-125) of intracellular water, 49 meq./kg. (range 40-56) of cellular mass, and 87 meq./kg. (range 62-112) of body solid. Intracellular Na averaged 37.0 meq./liter (range 31.3-43.5) of intracellular water, 17.6 meq./kg. (range 13.8-27.1) of cellular mass, and 35.7 meq./kg. (range 23.5-71.7) of body solid. The avg. values for intracellular K and Na concn. in man, as determined in this study, are in close agreement with comparable data obtained from studies in the dog and with estimates of intracellular electrolyte in man.