乌司他丁对急性坏死性胰腺炎大鼠肠黏膜屏障的保护作用

Protective mechanism of ulinastatin on mucosal barrier in rats with acute necrotizing pancreatitis

目的观察乌司他丁干预急性坏死性胰腺炎（ANP）大鼠后血TNF—α、二胺氧化酶（DAO）及肠黏膜组织紧密连接蛋白一1（zonulaoccludens-1，ZO-1）表达水平的变化，探讨其可能机制。方法按完全随机法将sD雄性大鼠随机分为假手术组、ANP组及乌司他丁组。采用5％牛磺胆酸钠逆行注入胆胰管的方法制模。制模后6、24h取血检测TNF-仪、DAO活性，胰腺及回肠组织常规病理检查，RT—PCR及免疫组化法检测回肠组织ZO-1mRNA及蛋白的表达。结果术后6h，ANP组胰腺大片坏死，大量炎细胞浸润；回肠黏膜绒毛上皮坏死、血管出血、炎细胞浸润。乌司他丁组的胰腺及回肠组织损伤较ANP组减轻。假手术组、ANP组、乌司他丁组术后6h的血TNF—α水平分别为（10．83±0．96）、（181．89±4．93）、（128．23±2．40）ng／L；DAO活性分别为（354．79±3．67）、（117．21±5．58）、（282．98±9．12）U／L；回肠组织ZO-1蛋白表达量分别为（10．00±1．87）、（1．20±0．84）、（5．80±2．86）分；ZO-1mRNA表达量为0．878±0．015、0．4664-0．023、0．7784-0．033。ANP组血TNF—Ot水平较假手术组明显升高，DAO活性、回肠组织ZO-1mRNA及蛋白表达较对照组明显降低（P值均〈0．05）；乌司他丁组的血TNF-α水平较ANP组降低，DAO活性、回肠组织ZO-1mRNA及蛋白表达较ANP组明显升高（P值均〈0．05）。结论乌司他丁可能通过抑制TNF-仪的过度释放、提高血浆中DAO活性，从而上调回肠组织中ZO-1mRNA和蛋白表达，进而保护肠黏膜屏障。

Objective To study the changes of serum levels of tumor necrosis factor-or （ TNF-α）, diamine oxidase （ DAO）, the expression of tight junction protein-1 （ zonula occludens 1, ZO 1 ） in acute necrotizing pancreatitis （ANP） rats after ulinastatin intervention. Methods SD male rats were randomly divided into sham operation （SO） group, ANP group and ulinastatin treatment group. ANP model was induced by injecting 5% sodium taurocholate into biliary and pancreatic duct. The rats were sacrificed at 6 and 24 hours, and then the levels of TNF-α, DAO and pathology change in pancreatic and intestinal were determined. The expression of bowel mucosa ZO-1 mRNA and protein was detected by RT-PCR and immunohistochemistry. Results Six hours after ANP induction, massive pancreatic necrosis and inflammatory cells infiltration were present, while epithelium necrosis of villi in ileum, vessel hemorrhage and inflammatory ceils infiltration was found. The pathologic injury of pancreas and ileum in ulinastatin group was reduced when compared with that in ANP group. The serum levels of TNF-α were （10.83 ±0.96）, （181.89 ±4.93）, （128.23 ±2.40）ng/L in SO group, ANP group and ulinastatin group; and the activities of DAO were （354.79 ± 3.67）, （117.21 ±5.58）, （282.98 ± 9.12） U/L; the expressions of ZO 1 protein were 10.00 ± 1.87, 1.20 ± 0.84, 5.80 ± 2.86 ; and the expressions of ZO 1 mRNA were 0. 878 ± 0. 015,0. 466± 0. 023, 0. 778 ± 0.033. The serum level of TNF-α in ANP group was significantly higher than that in SO group, while the activities of DAO, expressions of ZO 1 mRNA and protein in ileum were significantly lower than that in SO group （P 〈 0. 05 ）. The serum level of TNF-α in ulinastatin group was significantly lower than that in ANP group, while the activities of DAO, expressions of ZO 1 mRNA and protein in ileum were significantly higher than that in ANP group （ P 〈 0.05 ）. Conclusions Ulinastatin may inhibit the over release of TNF-α and improve plasma DAO activity, then increase the expression of ZO-1 mRNA and protein, thus protect the intestinal mucosa barrier.