Effects of sulfinpyrazone on renal function and prostaglandin formation in man

Sulfinpyrazone (800 mg/day for 6 days) significantly reduced the excretion of the main urinary prostaglandin E metabolite by 54% in 6 healthy female volunteers. While sulfinpyrazone did not affect inulin clearance, clearances of creatinine and PAH were significantly diminished by 18.0 and 44.7%, respectively. In the anaesthetized dog sulfinpyrazone decreased PAH clearance and PAH extraction concomitantly without affecting renal blood flow. These results show that clearances of creatinine and PAH do not reliably reflect glomerular filtration and renal perfusion, respectively, during sulfinpyrazone administration. Whereas sodium balance and body weight were not significantly different between the first control period and sulfinpyrazone administration, net sodium excretion significantly increased from 121.6 +/- 5.4 mEq/day during sulfinpyrazone treatment to 139.3 +/- 6.6 mEq/day during the following control period, while body weight significantly decreased indicating modest sodium retention during drug administration. Plasma renin activity, vascular sensitivity to angiotensin II, and urinary excretion of the enzymes N-acetylglucosaminidase and alanineaminopeptidase were not affected by sulfinpyrazone administration. In summary, sulfinpyrazone caused a decrease of total body prostaglandin E formation in healthy female volunteers together with a moderate sodium retention. Despite inhibition of prostaglandin synthesis, glomerular filtration rate, plasma renin activity, or pressor effects of angiotensin II were not altered.