THE EFFECT OF DESOXYCORTICOSTERONE ACETATE ON WATER AND ELECTROLYTE DISTRIBUTION 1 By A. Y. SWEET, M. F. LEVITT, AND H. L. HODES WITH THE TECHNICAL ASSISTANCE OF H. HABER AND B. KURZMAN

Previous evidence has indicated that in dog and man, the administration of adrenal hormones effects a temporary shift of sodium, chloride, and water in iso-osmotic proportions into the extracellular fluid (1, 2). This conclusion was based on the assumption that inulin afforded a reliable measure of the volume of the fluid phase of the extracellular compartment (3). It has been contended that after the administration of adrenal hormones a molecule like inulin might enter areas from which it was previously excluded (4). In this event, the increased volume of distribution of inulin would not reflect an expanded extracellular volume but rather a change in tissue permeability to inulin. To test the validity of the original conclusion, similar experiments were repeated in monkeys. In this protocol inulin spaces were measured before and after five days of desoxycorticosterone acetate (DCA) administration to monkeys. As in the experiments previously cited (1, 2), the animals were maintained on a low salt intake so that any expansion of the inulin space could not be attributed to retention of salt. In these experiments, however, sodium, chloride, potassium, and water content of muscle were studied in control animals and in those subjected to DCA administration. Tissue electrolyte composition was measured to determine whether the expanded inulin space would be associated with a comparable increase in sodium and chloride content of muscles. Such a correspondence would strongly favor the hypothesis that the extracellular volume had actually increased. Alternatively, it would be difficult to accept the presence of an expanded extracellular volume without a proportional increase in the salt content of muscle. It has been demonstrated that the stimulus of severe and uncompensated acidosis evokes a rapid