Objective:To study the effect of electrical stimulation of efferent vagus nerve on the acute liver injury induced by endotoxemia in rabbits. Methods:Sixteen rabbits were randomly divided into stimulation group(Group ...Objective:To study the effect of electrical stimulation of efferent vagus nerve on the acute liver injury induced by endotoxemia in rabbits. Methods:Sixteen rabbits were randomly divided into stimulation group(Group A,n=8) and control group (Group B,n=8).They were subjected to bilateral cervical vagotomy and intravenously challenged by lipopolysaccharide (LPS) (E.coli 0111:B4,DIFCO,USA) at a dose of 100 μg/kg injected within 30 min.The distal end of the left vagus nerve trunk was placed across bipolar electrodes connected to a stimulation module and controlled by an acquisition system.Stimuli with constant voltage (10V,5Hz,5ms) were applied twice to the nerve for 10 min before and after the administration of LPS in Group A.At the time 30,60,120,180,240,300 min before and after infusion of LPS respectively in each animal,blood samples were taken for late measurement of the serum Alanine aminotransferase (ALT),Aspartate aminotransferase (AST),tumor necrosis factor-α(TNF-α) and interleukin-10 (IL-10).Immediately after the experiment was finished,autopsy was performed and liver samples were taken to pathologic study. Results:Compared with Group B,the electrical stimulation of efferent vagus nerve could significantly decrease the contents of ALT,AST and TNF-α,but increase the contents of IL-10,in serum of Group A.It could also alleviate inflammation of liver tissue after LPS attack. Conclusion:The results suggest that excitation of the efferent vagus nerve can inhibit the inflammation cascade in liver after LPS challenge.Thus,it might have a protective effect on acute liver damage caused by endotoxemia.展开更多
Objective: To observe tissue distribution and cell localization of TNF α mRNA and its protein and study their role in the pathogenesis of liver injury in burn rats. Methods: An animal model of rats subjected to 2...Objective: To observe tissue distribution and cell localization of TNF α mRNA and its protein and study their role in the pathogenesis of liver injury in burn rats. Methods: An animal model of rats subjected to 20% TBSA Ⅲ degree burns combined with intraperitoneal injection of lipopolysaccharide (LPS) was used for this experiment. The changes of hepatic morphology and functions and serum TNF α content and expression and localization of liver TNF α and TNF α mRNA were determined with light microscope (LM) and electron microscope (EM), quantitative analysis, immunohistochemistry (IHC) and in situ hybridization (ISH). Results: It showed that there were sinusoid reaction, KCs activation and degeneration, necrosis of HCs, and platelets aggregation, fibrins deposition and PMNs attachment in sinusoid. The activity of ALT was obviously elevated and ALB content was slightly decreased. The serum content of TNF α showed peak at 3 hours. TNF α was mainly localized in sinusoid endothelial cells (SECs) and Kupffer cells (KCs), and TNF α mRNA was mainly distributed in KCs, polymorphonuclears neutrophils (PMNs) and macrophages (MPs). Conclusions: It suggests that TNF α mRNA and its protein expression and localization are coincident with the pathological changes of liver injury. TNF α is one of the key cytokines in the pathogenesis of liver injury in burn rats with endotoxemia.展开更多
文摘Objective:To study the effect of electrical stimulation of efferent vagus nerve on the acute liver injury induced by endotoxemia in rabbits. Methods:Sixteen rabbits were randomly divided into stimulation group(Group A,n=8) and control group (Group B,n=8).They were subjected to bilateral cervical vagotomy and intravenously challenged by lipopolysaccharide (LPS) (E.coli 0111:B4,DIFCO,USA) at a dose of 100 μg/kg injected within 30 min.The distal end of the left vagus nerve trunk was placed across bipolar electrodes connected to a stimulation module and controlled by an acquisition system.Stimuli with constant voltage (10V,5Hz,5ms) were applied twice to the nerve for 10 min before and after the administration of LPS in Group A.At the time 30,60,120,180,240,300 min before and after infusion of LPS respectively in each animal,blood samples were taken for late measurement of the serum Alanine aminotransferase (ALT),Aspartate aminotransferase (AST),tumor necrosis factor-α(TNF-α) and interleukin-10 (IL-10).Immediately after the experiment was finished,autopsy was performed and liver samples were taken to pathologic study. Results:Compared with Group B,the electrical stimulation of efferent vagus nerve could significantly decrease the contents of ALT,AST and TNF-α,but increase the contents of IL-10,in serum of Group A.It could also alleviate inflammation of liver tissue after LPS attack. Conclusion:The results suggest that excitation of the efferent vagus nerve can inhibit the inflammation cascade in liver after LPS challenge.Thus,it might have a protective effect on acute liver damage caused by endotoxemia.
文摘Objective: To observe tissue distribution and cell localization of TNF α mRNA and its protein and study their role in the pathogenesis of liver injury in burn rats. Methods: An animal model of rats subjected to 20% TBSA Ⅲ degree burns combined with intraperitoneal injection of lipopolysaccharide (LPS) was used for this experiment. The changes of hepatic morphology and functions and serum TNF α content and expression and localization of liver TNF α and TNF α mRNA were determined with light microscope (LM) and electron microscope (EM), quantitative analysis, immunohistochemistry (IHC) and in situ hybridization (ISH). Results: It showed that there were sinusoid reaction, KCs activation and degeneration, necrosis of HCs, and platelets aggregation, fibrins deposition and PMNs attachment in sinusoid. The activity of ALT was obviously elevated and ALB content was slightly decreased. The serum content of TNF α showed peak at 3 hours. TNF α was mainly localized in sinusoid endothelial cells (SECs) and Kupffer cells (KCs), and TNF α mRNA was mainly distributed in KCs, polymorphonuclears neutrophils (PMNs) and macrophages (MPs). Conclusions: It suggests that TNF α mRNA and its protein expression and localization are coincident with the pathological changes of liver injury. TNF α is one of the key cytokines in the pathogenesis of liver injury in burn rats with endotoxemia.