Relation of Sodium,Potassium,and Chloride Intake to Cortisone Action During Food Restriction

Abstract

Summary

1. Caloric requirements, water intake, and organ weights were determined for rats whose weights had been kept constant by restricted feeding of diets low in Na, K, and or CI with and without cortisone acetate. 2. Whereas ordinarily requirements for weight maintenance decline sharply during the first 5 weeks and become constant thereafter, little if any decrease was noted without Na and K salts. With cortisone, requirements for all diets except those containing CaCl₂ or NH₄C1 were initially much higher than without cortisone but went down rapidly. However, with NaCl and cortisone, the requirements were higher than with K salts or NaHCO₃ and cortisone. On CaCl₂, the requirements were reduced by cortisone. 3. The water intake of animals receiving neither Na nor K was very high. Cortisone reduced the intake of the CaCl₂-supplemented rats. The opposite effect was noted with NaCl. 4. Organ weight determination reaffirmed that the increase in kidney weight noticed on NaCl-containing, K salt-low diets could be avoided by replacement of NaCl by NaHCO₃. The renal changes were therefore not the consequence of simple K deficiency. Cortisone enhanced renal enlargement in animals on K salt-low, XaCl-containing diets. 5. Cortisone acetate and NaCl reinforce, under certain conditions, some of each other's actions.