| Objective: To observe whether the protective mechanism of dexmedetomidine(Dex)on hepatocytes in obstructive jaundice(OJ)rats is related to the activation of PI3K/Akt signaling pathway,and the PI3K/Akt specific inhibitor LY924002 To detect the role of PI3K/Akt signaling pathway in Dex inhibition of hepatocyte apoptosis in obstructive jaundice;to understand the correlation between the expression level of apoptosis-related gene Bcl-2/Bax and hepatocyte apoptosis in obstructive jaundice rats;Hope to prevent and treat liver damage caused by clinical obstructive jaundice and provide new ideas in liver protection drugs.Methods: 1.A total of 40 healthy male Wistar rats were selected,weighing 220-270 g,7-9weeks old.The random number table method was divided into 4 groups: sham operation group(S group),obstructive jaundice group(OJ group),dexmedetomidine group(DEX group),LY294002+ dexmedetomidine group(L group).Rats with obstructive jaundice were prepared in groups OJ,D,and L.Group S only separated the common bile duct and closed the abdomen layer by layer.In the DEX group,dexmedetomidine 100ug/kg was intraperitoneally injected 72 h after model establishment.The S group and the OJ group were injected with0.9% sterile saline at the same time point,and the L group was pumped through the tail vein10 minutes before the Dex(Pumping time 10 min)PI3K inhibitor LY294002(10% DMSO configuration 10 mmol / L)0.3 mg / kg.2.Three groups of rats were sacrificed 3 hours after injection,and the right outer lobe of the liver was taken out.The hepatocyte apoptosis index(AI)was determined by TUNEL method,and the expression levels of Akt and phosphorylated Akt(p-Akt)in liver tissue were detected by Western Blot.The number of Bcl-2 and Bax positive cells in liver tissue was determined by immunohistochemistry.Results: 1.General condition of the rat: The successful establishment of the rat model of obstructive jaundice was marked by the fact that the rat did not die.The upper part of the ligated common bile duct was obviously dilated and filled with bile,and the liver was obviously congested and congested.Rats died of various causes,and the common bile duct was ruptured,which was excluded by gross and pathological observation.If the number of rats is reduced due to the above reasons,the original standard rats should be replenished in time to ensure the actual number of experimental rats.Three days after the establishment of the experimental rat model,the OJ group,the DEX group and the L group were generally in poor condition compared with the S group,the appetite was significantly decreased,the urine color was dark yellow,and the hair color of the auricle and tail was less.Yellow,red sclera becomes shallower.3.2.Liver pathological changes: Compared with normal liver tissue morphology,there was no significant difference in the infiltration of small amounts of inflammatory cells in group S liver cells.The tissue structure of hepatic lobule disappeared in OJ group,massive accumulation of biliary pigment,hepatic sinus congestion,portal vein and interlobular vein hyperplasia with dilatation,hepatocyte necrosis accompanied by massive inflammatory cell infiltration;hepatocyte morphology in DEX group was normal compared with OJ group,and hepatic sinus congestion was less Inflammatory cells infiltrate less,but the portal vein and lobular veins still proliferate.The morphology of hepatocytes in group L was abnormaler than that in DEX group,hepatic sinus congestion increased,and inflammatory cell infiltration increased.3.The effect of dexmedetomidine(Dex)on hepatocyte apoptosis in rats with obstructive jaundice: Compared with the S group,the TUNEL value of hepatocytes in the OJ group was significantly increased,and the difference was statistically significant.(P<0.05);Compared with the OJ group,the TUNEL value of the liver cells in the DEX group was significantly less than that in the OEX group(P<0.05);compared with the simultaneous phase of the DEX group.The value of TUNEL in hepatocytes of group L was increased compared with the previous one(P<0.05).4.The effect of dexmedetomidine(Dex)on the expression of Bcl-2 and Bax in the liver tissue of rats with obstructive jaundice: Compared with the S phase,the expression of Bcl-2 and Bax in the liver tissue of OJ group was significantly increased.The difference was statistically significant(P<0.05).Compared with the OJ group,the expression of Bcl-2 was up-regulated and the expression of Bax was down-regulated in the DEX group(P<0.05).Compared with the DEX group,the expression of Bcl-2 was down-regulated and the expression of Bax was up-regulated in the liver tissues of rats ingroup L(P<0.05).5.Effect of dexmedetomidine(Dex)on the expression of Akt and p-Akt in liver tissue of rats with obstructive jaundice: Western blot results showed that p-Akt was expressed in different degrees in liver tissues of all groups,but total Akt The protein content did not change much.Compared with the S group,the expression of p-Akt protein in the liver tissue of OJ group was significantly up-regulated,the difference was statistically significant(P<0.05).Compared with the OJ group,the liver tissue of DEX group The p-Akt was significantly up-regulated,and the difference was statistically significant(P<0.05).Compared with the simultaneous phase of the DEX group,the expression in the liver tissue of the L group was decreased(P<0.05).Conclusion: In summary,dexmedetomidine can improve the damage of liver tissue structure caused by obstructive jaundice and reduce the apoptosis of hepatocytes,which may make p-Akt in liver tissue by activating PI3K/Akt signaling pathway.Increased expression,up-regulation of Bcl-2 protein expression,down-regulation of Bax protein expression,inhibition of hepatocyte apoptosis in obstructive jaundice,but still need to further explore the exact mechanism of dexmedetomidine in anti-apoptosis. |
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