Toll样受体9信号通路在重症急性胰腺炎大鼠肠黏膜屏障功能障碍中的作用

Role of Toll- like receptor 9 signaling pathway on intestinal mucosal barrier in rats with severe acute pancreatitis

目的探讨Toll样受体9(TLR9)信号通路在重症急性胰腺炎(SAP)大鼠肠黏膜屏障功能障碍发病过程中的作用。方法 24只SD大鼠随机分成观察组(n=18)和对照组(n=6)。观察组采用牛磺胆酸钠逆行注射胰胆管诱导SAP模型,对照组采用生理盐水代替牛磺胆酸钠胰胆管注射。观察组分别在造模后6、12、24 h活杀,每个时间点活杀6只,对照组造模后24 h活杀,分别取回肠黏膜组织检测TLR9的表达情况和核因子-κB(NF-κB)的活性,取外周静脉血测定血清淀粉酶(AMS)、二胺氧化酶(DAO)、D-乳酸(D-Lac)、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平,取胰腺和小肠组织进行病理评分,比较两组各项指标的差异。结果观察组各时间点小肠组织TLR9表达和NF-κB活性均显示高于对照组(P<0.05),血清AMS、DAO、D-Lac、TNF-α和IL-6水平也明显高于对照组(P<0.05),胰腺组织和小肠组织病理评分也明显高于对照组(P<0.05)。TLR9与NF-κB有较高的相关性(r=0.619,P<0.05),NF-κB与TNF-α也有较高的相关性(r=0.683,P<0.05)。结论 TLR9信号通路通过调节炎症介质水平,在SAP大鼠的肠黏膜屏障功能障碍发病过程中起着重要作用。

Objective To investigate the role of Toll - like receptor 9 （TLR9） signaling pathway on intestinalmucosal barrier in rats with severe acute pancreatitis （SAP）. Methods Twenty -four Sprague Dawley （SD） rats wererandomly allocated into control group （Group D, n = 6） and experimental group （Group S, n = 18 ）. Sodium taurocholate（4. 5% ） was injected into the pancreatic duct to induce SAP model in Group S, while replaced normal saline was given inGroup D. Each six rats in Group S were sacrificed 6, 12 and 24 hours after modeling, while all rats in Group D were sac-rificed 24 hours after modeling. Pancreas and intestine samples were collected for pathologic determination. The serumlevels of AMS, DAO, D - Lac, TNF - a and IL - 6 were measured using ELISA. A fluorescent RT - PCR or ELISA wasused to determine the levels of TLR9 and NF - κB in gut mucosa. Results The levels of TLR9 and NF - KB in Group Swere significantly higher than those in Group D, as well as the serum levels of AMS, DAO, D - Lac, TNF - a and IL -6. TLR9 was significantly correlated with NF - KB （ r = 0. 619, P 〈 0. 05 ） , as NF - KB was significantly correlated withTNF- a（r = 0. 683, P 〈 0. 05 ）. Conclusion TLR9 signaling pathway in gut mucosa can modify inflammatory cyto-kines, which may take an important role in intestine mucosal barrier.