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

Abstract

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. Renal hemodynamics and tubular function were assessed by clearance techniques, before and after 100-microgram, 200-microgram, 400-microgram, or 800-microgram oral doses of misoprostol. 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-microgram 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. 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-micrograms of misoprostol suggests that it may be of therapeutic value in patients with cirrhosis.