The Study On Relationship Between NF-κB And Hepatic Injury Of Baby Rats Induced By Endotoxemia And Intervention By Glutamine

Objective:Through the establishment of animal model of endotoxemia,to detect the activation of NF-κB and the level of TNF-αand IL-6 in liver,and to investigate the relationship of NF-κB activation and hepatic injury.To give glutamine intervention,research its role in hepatic injury.Method:72 rats of 18-day-postnatal were randomly divided into normal control group(NS,n=8),lipopolysaccharide group(LPS,n=32)and glutamine group(Gln,n=32).In LPS group and Gln group,baby rats were injected lipopolysaccharide into abdominal cavity at a dose of 5mg/kg,Gln group was given Gln(2g/kg)by mouth at the same time.In NS group,5mg/kg Sodium Chloride was injected.On the basis of the survival time after injected lipopolysaccharide,LPS group and Gln group were divided into 2,6,12 and 24 hours secondary groups.Each secondary group of 8 rats.The rats were executed after injured 2,6,12,24 hours and blood removed from the vena was analyzed for ALT by colorimetry.Hepatic tissue was collected to make into paraffin section and homogenate.The level of TNF-αand IL-6 were detected by ELISA and the activation of NF-κB by immunohistochemistry.The pathological change of hepatic tissue was observed by light microscope and electron microscope.The results were analyzed statistically.Results:1.The level of ALT in LPS group began to increase after 2 hours, arrived at peak on 12 hours.And the level was significant higher than NS group on 6,12,24 hours(p＜0.05).Gln group arrived to its peak on 12 hours too,the level of ALT was significant higher than NS group(p＜0.05),compared to LPS group on 12,24 hours,the level of ALT was lower(p＜0.05).2.The expression of NF-κBp65 in LPS group got a peak on 2 hours,and then it decreased gradually,24 hours started to rise again.The expression was significant higher than NS group(p＜0.05)in each phase,the same as Gln group, and the expression of Gln group was lower than LPS group on 2,6 hours(p＜0.05).3.The level of TNF-αand IL-6 in LPS group and Gln group got a peak on 6 hours simultaneously and were significant higher than NS group(p＜0.05).In LPS group,the level of TNF-αon 6,12 hours and the level of IL-6 in each phase were higher than NS group(p＜0.05),In Gln group,the level of TNF-αon 6 hours and the level of IL-6 on 6,24 hours were higher than NS group(p＜0.05), and the level of TNF-αon 12 hours and the level of IL-6 on 2,12,24 hours were lower than LPS group(p＜0.05).4.The pathological change of liver tissues in LPS group was showed vacuolar degeneration,inflammatory cell infiltration,patchy hemorrhagic necrosis.The structural of hepatic lobules were damaged.6 hours was the worst piont.Under electron microscope,LPS group showed vacuolar degeneration of liver cells,the chondriosome was swelled and the crista was reduced.The endoplasmic reticulum was expanded,chromatin agglutination lied in the margin of nucleus.Gln group alleviated the above-mentioned pathological changes significantly.Conclusion:1.After the attack by LPS,serum ALT increased,pathological changes in hepatic tissue was significant,successfully established a model that endotoxemia cause hepatic injury in baby rats.2.The activation of NF-κB might participate in the hepatic injury by endotoxemia.That might be lead to the excess creation of inflammation mediators TNF-αand IL-6 which caused the inflammatory damage.3.Glutamine could significantly reduce the LPS-induced hepatic injury,and its mechanism might be through inhibiting the activation of NF-κB and decreasing the production of TNF-αand IL-6.