FORMATION OF SUPEROXIDE ANION IN THE HEPATIC SINUSOID AFTER LIPOPOLYSACCHARIDE CHALLENGE

Using the cytochrome c method, superoxide anion that is released into the hepatic sinusoid was measured after a lipopolysaccharide challenge in a liver perfusion system. Moreover, damages of epithelial cells of the hepatic sinusoid were estimated with scanning electron microscopi c analysis and levels of purine nucleoside phosphorylase/GPT ratio. Li popolysaccharide administration increased the conversion of oxidized c ytochrome c into reduced cytochrome c in the perfusate, indicating tha t superoxide anion was formed in the hepatic sinusoid. This change was associated with increase in levels of portal tumor necrosis factor-al pha and attenuated by the simultaneous administration of superoxide di smutase, Scanning electron microscope analysis revealed that diameters of sinusoidal fenestrae increased in rats treated with lipopolysaccha ride, compared with controls. Moreover, levels of purine nucleoside ph osphorylase/GPT ratio was significantly increased in the liver perfusa te in lipopolysaccharide-treated rats, compared with controls. Superox ide anion in hepatic sinusoid may be one of the pathogenic factors beh ind damages of epithelial cells of the hepatic sinusoid caused by lipo polysaccharide.