METABOLIC-FATE OF ENDOTOXIN AND BLOOD TUMOR-NECROSIS-FACTOR LEVELS IN RATS WITH ACUTE AND CHRONIC ALCOHOL LOADING

To investigate the metabolic fate of endotoxin in alcoholics and its possible relationship to cytokines and liver injury, we administered a low-dose radiolabelled endotoxin to rats given alcohol in various conditions and studied the organ distribution of endotoxin and measured plasma levels of tumour necrosis factor (TNF). In the chronic alcohol-fed rats (Lieber-DeCarli liquid diets for 6 weeks) H-3-endotoxin was rapidly cleared by the liver and excreted into faeces. However, the endotoxin clearance was decreased after an acute ethanol load to rats (5 mg/g body wt ethanol i.p.) or in the chronic ethanol-fed rats with an additional 5 mg/g body wt ethanol load. Plasma, TNF was not elevated in the control or in the acute ethanol load rats, slightly elevated in the chronic ethanol-fed rats and markedly elevated in the chronic ethanol-fed rats with an additional high-dose ethanol load. Serum GPT was elevated only in the chronic ethanol-fed rats with an additional high-dose ethanol. In conclusion, an additional administration of a high dose ethanol to chronic alcohol-fed rats led to decrease of endotoxin clearance and elevation of plasma TNF, which may play an important role in the pathogenesis of alcoholic hepatitis.