蛋白激酶C-核转录因子信号通路在急性胰腺炎肝损伤中的作用

The significance of protein kinase C-nuclear factor-κB pathway in sever acute pancreatitis-associated hepatic injury in rats

目的 观察蛋白激酶C（PKC）-核转录因子（NF-κB）通路在急性胰腺炎肝损伤发生过程中的作用.方法 将90只雄性SD大鼠随机分为3组,即假手术正常对照组（P组）、胰腺炎组（S组）和干预组（H-7治疗组,H组）,每组30只.采用胰胆管逆行穿刺注射5％牛磺胆酸建立大鼠急性坏死性胰腺炎模型.分别在建模后第2、6、12小时处死大鼠并采集肝脏组织和血清,采用免疫组织化学法检测肝组织中PKC-α和NF-κB的活性,用反转录-聚合酶链反应（RT-PCR）检测肝组织中PKC-α mRNA的表达,并应用放射免疫法检测血清中肿瘤坏死因子-α（TNF-α）的水平,生化检测血清中谷丙转氨酶（ALT）的含量.结果 H组大鼠血清中TNF-α在2、6、12 h的含量分别为（0.733 6 ±0.026 6）、（0.787 0±0.020 6）、（0.862 0±0.026 2）μg/L,较S和P组显著降低,差异有统计学意义（P＜0.05）.H组大鼠肝组织中NF-κB在2、6、12 h阳性表达细胞的百分率分别为（33.534 6±2.049 1）％、（46.916 3±2.252 7）％、（57.868 5±2.195 8）％,较S和P组比较显著降低,差异有统计学意义（P＜0.05）.H组大鼠肝组织中2、6、12 h PKC-α mRNA表达分别为1.164 6 ±0.016 2、1.189 5±0.015 5、1.207 1±0.0165,PKC-α蛋白阳性表达分别为83.988 0±1.2466、86.406 0±1.248 1、89.858 0±1.245 1,较S组和P组明显降低,差异有统计学意义（P＜0.05）.结论 PKC-NF-κB通路在急性胰腺炎肝损伤发生过程中发挥重要作用,抑制这一通路可以有效地减轻肝脏组织的损伤程度.

Objective The objective of the study was to evaluate the effect of protein kinase C （PKC）-nuclear factor-κB （NF-κB） pathway in ameliorating liver injury in rats with severe acutepancreatitis （SAP） and its possible mechanism.Methods A total of 90 male SD rats were randomly divided into three groups with 30 rats for each group,normal control group （sham operation group,P group）,acute pancreatitis group （model group,S group） and intervention group （H-7 treated group,H group）.The acute pancreatitis model in rats were induced by retrograde injection of 5％ sodium taurocholate into the pancreatobiliary duct.The liver samples were obtained at 2,6 and 12 hours respectively after operation and after being killed in each group.The activity of NF-κB and PKC-α in hepatic tissue were detected with immunohistochemistry and the expression of PKC-α mRNA in hepatic tissue was detected with reverse transcriptase-polymerase chain reaction （RT-PCR）.The level of serum tumor necrosis factor-α （TNF-α） was measured by radioimmunoassay （RIA） and the ALT was detected by biochemical method.Results The serum TNF-α in H group at 2,6,12 h were （0.7336±0.0266）,（0.7870± 0.020 6）,（0.862 0 ± 0.026 2） μg/L,reduced significantly than S and P group （P ＜ 0.05）.The percentage of positive expression cells of NF-κB in hepatic tissues at 2,6,12 h were 33.534 6 ± 2.049 1,46.916 3 ± 2.252 7,57.868 5 ± 2.195 8,lower than S and P group（P ＜ 0.05）.The expression of PKC-αmRNA in hepatic tissues at 2,6,12 h were 1.1646±0.0162,1.1895±0.015 5,1.207 1± 0.016 5,the positive protein expression of PKC-α were 83.988 0 ± 1.246 6,86.406 0 ± 1.248 1,89.8580±1.245 1,both lower than S and P group （P＜0.05）.Conclusion ThePKC-NF-κB pathway could play an important role in the severe acute pancreatitis-associated hepatic injury,which could be alleviated by suppressing the pathway.