Abstract: AIM: To investigate the effects of glycyrrhizin(GL) and dexamethasone( DEX) on alpha-naphthylisothiocyanate( ANIT) induced acute cholestasis in rats.METHODS: Acute cholestasis in rats was induced by ANIT, and the effects of GL and DEX on acute cholestasis were examined by serology determination, histological assessment of hepatic injury and bile excretion experiments.RESULTS: The protection of DEX pretreatment was directed toward cholangiocytes rather than hepatocytes.Rats remedially treated with DEX 3 h after ANIT administration were not resistant to ANIT toxicity.Notably,remedial treatment with DEX 12 h after ANIT enhanced ANIT toxicity.However, GL attenuated both bile duct and hepatocyte damage induced by ANIT in the initial phase of impairment.CONCLUSION: GL exhibited better protection against ANIT-induced acute cholestasis than DEX.In the initial phase of impairment of acute cholestasis, the protection of GL maybe partially due to modifications of metabolism and excretion of ANIT and anti-inflammatory effect.

Key words: glycyrrhizin, dexamethasone, alphanaphthylisothiocyanate, intrahepatic cholestasis