FURTHER NOTES ON THE INTERACTION OF SPIRONOLACTONE AND DEOXYCORTICOSTERONE ACETATE IN DOGS

Abstract
Adminstration of DCA induced typical mineralocorticoid effects in a dog, namely the retention of urinary Na and Cl and the loss of K ions. Coadministration of spironolactone orally at several doses neutralized the effect on K, but produced a rate-limited inhibition of Na and Cl retention, by altering tubular reab-sorption of the ions. Plasma levels of spironolactone did not appear to be a factor limiting the Na and Cl response. Interpretation of these data indicates that spironolactone inhibited only one of the tubular reabsorb-ing mechanisms for renal effects of DCA.