RESUMEN
AIM: To study the role of liver in immune regulation in experimental endotoxemia. METHODS: 17 castrated male goats were subjected to simultaneously installing catheters in jugular, hepatic and portal veins by surgery. Four days later, lipopolysaccharide (LPS) was infused in term of three groups as followings: In group ①, LPS of 20 EU (endotoxin unit, EU)?kg -1 was infused into portal vein; In group ②, LPS of 20 EU?kg -1 was infused into jugular vein and LPS of 1 500 EU?kg -1 infused into jugular vein in group ③. Before and after infusion, blood samples were collected from the three veins through the catheters for 8 h. The plasma levels of TNF-? were measured by RIA. RESULTS: In group ①, the plasma TNF-? levels of hepatic and portal vein rose to peak value at 5 h, but that of the jugular vein did not changed. In group ②, the plasma TNF-? levels in hepatic vein rose to peak value at 3 h. The TNF-? levels of jugular vein rose to peak value at 1 h and the one in portal vein enhanced continuously between 0-8 h. In group ③, the plasma TNF-? levels in jugular, hepatic and portal vein rose to significant peaks at 1 h simultaneously. CONCLUSION: During experimental endotoxemia,liver showed different dynamic characteristics in TNF-? secretion according to the pathway and doses of LPS delivery. [