Glycyrrhizin ameliorates renal function defects in the early-phase of ischemia-induced acute renal failure

The aim of this study was to investigate the effect of glycyrrhizin administration (200 mg/kg/day) on renal function parameters in the early‐phase of ischaemia‐reperfusion induced acute renal failure (ARF) in rats. The present study showed that the urinary flow rate in ischaemia‐ARF was significantly increased in association with decreases in water balance, urinary sodium excretion and urine osomolality, which were partially restored by administration of glycyrrhizin. Both solute‐free water reabsorption (TcH2O) and creatinine clearance (Ccr) were significantly decreased in rats subjected to ischaemia‐reperfusion for 72 h compared with the control. Histopathological examination of the kidneys from ARF rats at 72 h after release of the bilateral renal artery clamping, showed that the glomerulus, proximal tubules and distal tubules were severely disrupted and left a denuded basement membrane. When glycyrrhizin was administered in rat ARF for 72 h, Ccr reached almost 96% compared with that of the sham‐operated control rats and TcH2O was improved by 47% compared with that of the ischaemia‐ARF rats. The lesions in the glomerulus, proximal and distal tubule of the renal cortex were also restored by the administration of glycyrrhizin. Taken together, glycyrrhizin administration ameliorates both renal function defects, especially the renal concentrating ability, and structural lesions in renal tissues in rats in the early‐phase of ischaemia‐ARF. Copyright © 2003 John Wiley & Sons, Ltd.