ION ASSOCIATION. IV. EFFECT OF SODIUM SULFATE INFUSION ON RENAL CLEARANCE AND BODY RETENTION OF INJECTED RADIOSTRONTIUM IN DOGS*

Abstract

Carrier-free isotopes of strontium, Sr85 and Sr89, were injected intravenously into dogs. At intervals of 2.5 to 168 hours later, solutions containing sulfate were infused for 2 to 20 hours. The rate of urinary radiostrontium excretion immediately increased 6- to 40-fold. Radiostrontium clearance per 100 ml of glomerular filtrate increased linearly with sulfate excretion. The fraction of filtered strontium excreted reached 80% as compared with a normal value of less than 10%. During sulfate infusion, 22 to 50% of the isotope remaining was excreted in the urine, providing that therapy was instituted within 18 hours of infection. When therapy was delayed, less than 15% of the remaining radiostrontium was removed. In half of the experiments, the amount of isotope excreted in the urine during sulfate infusion was more than twice the amount estimated to be in the extracellular fluid, indicating that deposits of radiostrontium were mobilized from the skeleton and/or tissues.