【摘要】 目的探讨NF-κB在大鼠肝缺血再灌注损伤与缺血预处理(IPC)保护机制中的作用。方法将72只SD雄性大鼠随机分成4组:缺血再灌注损伤组(I/R组);缺血预处理组(IPC组);NF抑制剂组(应用二硫代氨基甲酸吡咯烷即PDTC组);假手术组(S组)。测定血清丙氨酸氨基转移酶(ALT),天冬氨酸氨基转移酶(AST),乳酸脱氢酶(LDH)活性;测定肝脏的湿干比(W/D);经HE切片染色后,观察肝组织显微结构;分别应用免疫组化和Western blot免疫印迹法测定肝组织中的TNF-α和NF-κB表达。结果 I/R组大鼠血清肝酶学指标(AST、ALT、LDH)和肝脏的组织形态学都显示较S组大鼠有明显的肝脏损伤。同时肝组织W/D比值和TNF-α的阳性表达比及NF-κB在免疫组化和western blot免疫印迹中的表达亦均明显高于S组(P<0.01)。IPC组和PDTC组大鼠肝损伤程度明显轻于I/R组,同时TNF-α和NF-κB在两种检测方法中的表达亦均明显低于I/R组(P<0.05)。结论 NF-κB在肝I/R损伤的发生机制中是细胞信号传导通路上的重要转录因子,对I/R损伤的炎症反应起介导作用;NF-κB的活化被抑制是肝IPC保护机制中的重要环节;针对NF-κB的靶向治疗是临床肝保护有意义的新途径。更多还原

【Abstract】 Objective To investigate the role of NF-κB in the mechanism of ischemia-reperfusion(I/R)injury and protection of ischemic preconditioning(IPC) for liver in rats.Methods Seventy-two male SD rats were randomly divided into four large groups,and there’ re three small groups in each large group according to the reperfusion hours.(1) I / R group(n = 18);(2) IPC group(n = 18);(3) PDTC group(n = 18);(4) S group(n = 18) :animals were only subjected to anesthesia and laparotomy.At the end of I / R,blood and liver tissues samples were obtained,blood was used to determine the activities of alanine aminotransferase(ALT),aspartate transaminase(AST)and lactic dehydrogenase(LDH),the liver tissues were processed to:(1) detect the ratio of wet weight and dry weight of liver tissue with oven;(2) observe the microscopical structure of the liver tissue by HE staining;(3) analysis the expression of TNF-α in the liver tissues by immunohistochemistry;(4) determine the experssion of NF-κB by methods of immunohistochemistry and western blot.Results The activities of ALT,AST and LDH,and histomorphology of liver were all obviously damaged at the end of reperfusion respectively in the I / R group of rats.Meanwhile,the levels of W / D index,the positive ratios of TNF-α and the expressions of NF-κB in liver tissues detected by immunohistochemistry and western blot were all higher than those in S group(P < 0.01).Rats of IPC and PDTC groups were separately subjected to IPC and injection of PDTC,then an I / R of 2,3,4 hours respectively,appeared an obviously slighter damage than I / R group.Conclusion The signal path of NF-κB is involved in the mechanism of I /R injury and mediates the inflammation of I / R of liver in rats.The inhibition of NF-κB is an important link in the mechanism of IPC for liver in rats.NF-κB is a novel therapeutic target in protection of IPC for liver.更多还原