Dose-dependent effects of oral misoprostol on renal function in alcoholic cirrhosis

Abstract

Background/Aims: Prostaglandins are important modulators of renal physiology, particularly when the effective circulatory volume is decreased. The aim of this study was to determine the dose-dependent effects of an oral prostaglandin E1 analogue, misoprostol, on renal function in patients with well-compensated alcoholic cirrhosis. Methods: Renal hemodynamics and tubular function were assessed by clearance techniques, before and after 100-μg, 200-μg, 400-μg, or 800-μg oral doses of misoprostol. Results: Overall, the results indicate that low-dose misoprostol is vasodilatory, natriuretic, and diuretic whereas high-dose misoprostol increases renal vascular tone and inhibits sodium and water excretion. The 200-μg dose produced a transient but significant increase in the glomerular filtration rate and effective renal plasma flow and a decrease in renal vascular resistance. Urinary volume and urinary sodium excretion increased and urinary osmolality decreased. Conclusions: The results suggest that, in patients with well-compensated cirrhosis, the renal effects of misoprostol are determined by a bell-shaped dose-response curve. The renal vasodilatory, natriuretic, and diuretic potential of 200-μg of misoprostol suggests that it may be of therapeutic value in patients with cirrhosis.