细胞外调节蛋白激酶与核因子-κB活化对重症急性胰腺炎大鼠中性粒细胞凋亡延迟的调控作用

Role of extracellularly regulated kinase and nuclear factor-kappa B activation in regulating neutrophil apoptosis in rats with severe acute pancreatitis

目的探讨细胞外调节蛋白激酶和核因子-κB活化对重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠中性粒细胞凋亡延迟的调控作用。方法 60只雄性SD大鼠随机分为对照组、SAP组、吡咯烷二硫代氨基甲酸盐(pyrrolidine thiocarbamate,PDTC)组(CPTC组)和细胞外调节蛋白激酶特异性抑制剂PD98059组各15只,对照组大鼠仅作开腹再缝合,SAP组、PDTC组和PD98059组大鼠采用胆胰管逆行注射质量分数4%牛磺胆酸钠建立SAP模型,PDTC组和PD98059组大鼠造模前分别注射PDTC和PD98059,对照组和SAP组仅注射等量生理盐水。24h后于大鼠下腔静脉取血分离中性粒细胞,体外培养16h后采用流式细胞仪检测中性粒细胞凋亡率和Bcl-xl基因表达情况。结果体外培养16h后,SAP组中性粒细胞凋亡率明显低于对照组、PDTC组和PD98059组(P<0.01),Bcl-xl基因表达水平明显高于对照组、PDTC组和PD98059组(P<0.01);PDTC组和PD98059组中性粒细胞凋亡率低于对照组(P<0.01);PD98059组Bcl-xl基因表达水平高于对照组(P<0.01),PDTC组与对照组比较差异无统计学意义(P>0.05)。结论 SAP时大鼠中性粒细胞中Bcl-xl表达明显增加,导致其自发凋亡率减低,PD98059或PDTC可明显抑制Bcl-xl表达,恢复其自发凋亡率。

Objective To investigate the role of extracellular regulated kinase （ERK） and nuclear factor-kappa B （NF-κB） activation in regulating neutrophil apoptosis in rats with severe acute pancreatitis （SAP）. Methods Sixty male SD rats Were randomly divided into control group, SAP group, PDTC group, and PD98059 group, with 15 rats in each group. SAP models were established by intrapancreatobiliary duct injection of 4% sodium taurocholate in SAP group, PDTC group and PD98059 group, while control group was opened and sutured the abdomen. Before establishment of models, PDTC group and PD98059 group were injected PDTC and PD98059 respectively, and control group and SAP group were only injected the same volume of normal saline. After 24 hours, inferior vena cava blood was collected for neutrophil cell separation, and was detected neutrophil apoptosis rate and Bcl-xl gene expression by flow cytometry after being cultured for 16 hours. Results After incubation in vitro for 16 hours, neutrophil apoptosis rate was significantly lower, and Bcl-xl was significantly higher in SAP group than that in control group, PDTC group and PD98059 group （P〈0.01）. The neutrophil apoptosis rate was lower in PDTC group and PD98059 group than that in control group （P〈 0.01）. The expression of Bcl-xl was higher in PD98059 group than that in control group （P〈0.01）, and there was no significant difference between PDTC group and control group （P 〈 0.05）. Conclusions The expression of Bcl-xl increases significantly in rats with SAP, leading to the desease of spontaneous apoptosis rate. Intravenous injection of PD98059 and PDTC can inhibit the expression of Bcl-xl, and restore the spontaneous apoptosis rate.