PT  - JOURNAL ARTICLE
AU  - Sastry, B. V. RAMA
AU  - Bush, Milton T.
TI  - ENHANCEMENT OF THE RENAL EXCRETION OF CESIUM-137 IN RATS TREATED WITH ACETAZOLAMIDE AND RELATED COMPOUNDS
DP  - 1964 Jan 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 30--41
VI  - 143
IP  - 1
4099  - http://jpet.aspetjournals.org/content/143/1/30.short
4100  - http://jpet.aspetjournals.org/content/143/1/30.full
SO  - J Pharmacol Exp Ther1964 Jan 01; 143
AB  - The renal excretion of Cs137 by the rat has been shown to be increased by carbonic anhydrase inhibitors (acetazolamide, ethoxzolamide), inhibitors of the H+ exchange system (maleate) and materials producing hyperchloremic acidosis (ammonium chloride). Our results support the view that Cs+ substitutes for K+ in the H+ exchange system. Meralluride blocked the effect of acetazolamide on Cs137 excretion without any influence on urine volume and pH. This indicates that acetazolamide increases the urinary excretion of Cs137 by increasing its secretion through the renal tubule in the same manner as it increases the excretion of K. Metabolic acidosis nullified the effect of acetazolamide on Cs137 excretion. The animals treated with ammonium chloride and the animals treated with ammonium chloride followed by acetazolamide excreted equal amounts of Cs137. With repeated doses of acetazolamide there was no continued increase in Cs137 excretion. This result is similar to the influence of the repeated doses of acetazolamide on K excretion. There seems to exist a relationship between the activities of the structural analogs of acetazolamide in their inhibition of carbonic anhydrase and their efficacies for increasing the urinary excretion of Cs137. Clinical doses of the very active carbonic anhydrase inhibitors, ethoxzolamide and acetazolamide, increased Cs137 excretion during the drug phase of 6 hours. Chlorothiazide is a weak carbonic anhydrase inhibitor. Large doses increased the Cs137 excretion during the drug phase of the first 1 hour. Clinical doses of hydrochlorothiazide, which do not inhibit carbonic anhydrase, did not increase Cs137 excretion. Maleate increased Cs137 and bicarbonate in urine during its drug phase of 6 hours. Acetazolamide increased Cs137 excretion and thereby decreased the retention in the muscle. Chlorothiazide increased Cs137 excretion during the first hour, but its cumulative effect was to decrease Cs137 excretion, and thereby favor accumulation of higher concentrations of Cs137 in the skeletal muscle. The Williams & Wilkins Company