AIM: To investigate the effects of intravenous administration of the antioxidant glutathione (GSH) on reperfusion injury following liver transplantation.METHODS: Livers of male Lewis rats were transplantedafter 24 h of hypothermic preservation in University of Wisconsin solution in a syngeneic setting. During a 2-h reperfusion period either saline (controls, n=8) or GSH administered via the jugular vein.RESULTS: Two hours after starting reperfusion plasma ALT increased to 1 457±281 U/L (mean±SE) in controls but to only 908±187 U/L (P＜0.05) in animals treated with morphological findings on electron microscopy: GSH treatment prevented detachment of sinusoidal endothelial cells (SECs) as well as loss of microvilli and mitochondrial swelling of hepatooytes. Accordingly, postischemic bile flow increased 2-fold. Intravital fluorescence microscopy revealed a nearly complete restoration of sinusoidal blood flow and a significant reduction of leukocyte adherence to sinusoids and postsinusoidal venules. Following infusion of 50 μmol and and 97±18 mol/L, but to only 20±3 mol/L in untreated recipients. Furthermore, plasma glutathione disulfide (GSSG) increased untreated controls (1.8±0.5 mol/L vs 2.2±0.2 mol/L).CONCLUSION: Plasma GSH levels above a critical level may act as a sink for ROS produced in the hepatic vasculature during reperfusion of liver grafts. Therefore, GSH can be considered a candidate antioxidant for the prevention of reperfusion injury after liver transplantation, in particular since it has a low toxicity in humans.