The Mechanism Of Dexmedetomidine-ulinastatin Combination On Liver Injury In Obstructive Jaundice Rats

Objective: To observe the infuences of dexmedetomidine and ulinastatin on liver function and the expression of inflammatory cytokines,then to explore the protective effects and mechanisms of dexmedetomidine-ulinastatin combination on liver injury in obstructive jaundice rats.Methods: Forty male SD rats weighting of 230 g ~ 270 g were randomly divided into 5 groups(n = 8).The five groups were sham operated(Sham)group,NS group,dexmedetomidine(DEX)treated group,ulinastatin(UTI)treated group and dexmedetomidine-ulinastatin combination(DEX+UTI)treated group.We collected the blood via the tail vein of rats and liver tissue,then we tested through these methods and related indexes: 1)The biochemical indicators of liver function including TBIL,ALT,AST and TP were measured by an auto-analyzer.2)The serum TNF-α and IL-6 was detected by using ELISA.3)The liver tissues were collected to evaluate the histological changes by using HE staining and to detect the expressions of TLR4 and NF-κB with immunohistochemical staining.4)TNF-α,IL-6,TLR4 and NF-κB in liver tissues were also determined by using q RT-PCR and western blot.Results: 1.The haematoxlin eosin(HE)staining results of liver tissue of each group in obstructive jaundice rats. Histological appearance of the liver in the sham group was normal.The NS group were markedly presented a severe and marked histologic damage of the liver.The hepatic cell occurred denaturation,edema and even widespread necrosis.In addition,the inflammatory cells infiltration,sinusoids dilation and intrahepatic bile duct proliferation were observed as well.Surprisingly,after the administration of DEX,UTI,and DEX+UTI,the histological appearances that existed in the NS group were markedly localized,which only part of the tissue were intrahepatic bile duct proliferation and vacuolar degeneration.2.The assay results of liver function of each group in obstructive jaundice rats.Compared with the Sham group,TBIL,ALT and AST levels of NS group,were significantly increased,TP levels were significantly decreased,the difference was statistically significant(p<0.001);compared with the NS group,in DEX group,UTI group and DEX + UTI group,TBIL,ALT and AST levels were significantly decreased,TP levels were significantly increased,the difference was statistically significant(p<0.001);DEX + UTI group is better than the DEX group and UTI group;compared with the DEX group,in UTI group,TBIL levels were significantly decreased,the difference was statistically significant,this difference between the two groups was not statistically significant(p>0.05).3.The ELISA assay results of serum TNF-α,IL-6 of each group in obstructive jaundice rats.Compared with the Sham group,in NS group,IL-6,TNF-α levels were significantly increased,the difference was statistically significant(p<0.001);Compared with the NS group,in DEX group,UTI group and DEX + UTI group,IL-6,TNF-α levels were significantly lower,the difference was statistically significant(p<0.001);DEX + UTI group is better than the DEX group and UTI group,which was no difference between statistically significant(p> 0.05).4.The Immunohistochemical(IHC)staining results of liver tissue of each group in obstructive jaundice rats.The Results showed that in the sham group,there were little or almost no expressions of TLR4 and NF-κB in hepatic tissues.As expected,in the NS group,the extensive staining of the two markers in liver tissues was obviously observed.Furthermore,after the application of DEX and UTI alone or in combination,all three types of treatment led to the decreased expressions of TLR4 and NF-κB.5.The q RT-PCR results of liver tissue expression of inflammatory cytokines of each group in obstructive jaundice rats.Real-time quantitative PCR showed that,at the m RNA level,the four inflammatory cytokines including IL-6,TNF-α,TLR4 and NF-κB of the NS group was significantly increased than Sham group,the difference was statistically significant(p<0.001).After being treated,they were reverted with varying degrees and more obviously reverted degree was observed in combination treatment group.In the DEX group and UTI group,there was no difference between statistically significant(p> 0.05).6.The western blot results of liver tissue expression of inflammatory cytokines of each group in obstructive jaundice rats.Compared with the Sham group,IL-6,TNF-α,TLR4 and NF-κB were significantly increased in the NS group,the difference was statistically significant(p<0.001);Compared with the NS group,DEX group,UTI group and DEX+UTI group of four inflammatory cytokines were significantly decreased,the difference was statistically significant(p<0.001).Between the three treatment groups,IL-6 and TNF-α in the combination group were significantly lower than the two alone groups,the difference was statistically significant;on the other hand,TLR4 and NF-κB in the DEX+UTI group relatively lower,but the difference was not statistically significant(p> 0.05).Conclusions: 1.DEX and UTI administered alone or in combination could protect against the liver injury that caused by the obstructive jaundice,which also significantly reduce the production and release of pro-inflammatory cytokines.2.The liver protection may possibly act through suppressing the TLR4/ NF-κB signaling pathway.3.The combination treatment is better than the single treatment while no obvious difference between the DEX and UTI treatment.