Hemin pretreatment ameliorates aspects of the nephropathy induced by mercuric chloride in the rat

Mercuric chloride (HgCl2) is known to be a nephrotoxicant. When HgCl2 is ad ministered into rats, acute renal failure (ARF) is induced. Heme oxygenase- l (HO-1) is antioxidative enzyme and is known to play a protective role aga inst the oxidative injury. To elucidate the cytoprotective role of HO-1 aga inst the nephrotoxicant-induced ARF, we examined the effect of hemin, HO-1 inducer, on HgCl2-induced ARF. Subcutaneous administration of hemin (30 mg/ kg body weight) into rats once a day for two successive days obviously indu ced HO-1 protein in the kidneys at 24 h after the last injection. Under thi s situation, when HgCl2 (1 mg/kg body weight) was intraperitoneally injecte d into rats at 24 h after the last injection of hemin improved the serum cr eatinine (SCr) and blood urea nitrogen (BUN) levels, markers for renal inju ry, at 24 h after the HgCl2 injection as compared with the control rats wit hout hemin pretreatment (HgCl2 treatment alone). This result was further co nfirmed by histopathological analysis. These findings strongly suggest that the preinduction of HO-1 ameliorates the subsequent HgCl2-induced acute re nal injury. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.