N-乙酰半胱氨酸对重症急性胰腺炎肠屏障作用的实验研究

目的:探讨N-乙酰半胱氨酸(NAC)对重症急性胰腺炎(SAP)肠屏障的作用及机制。方法:54只清洁健康雄性SD大鼠,随机分成假手术(Sham)组、SAP组和NAC+SAP3组,每组18只。建模后6、12、24h分批处死,采集腹主动脉血测定二胺氧化酶(DAO)及淀粉酶(AMY)含量;取胰腺和末端回肠标本进行组织病理诊断;小肠组织匀浆测定丙二醛(MDA)、还原型谷胱甘肽(GSH)和超氧化物歧化酶(SOD)水平。结果:与Sham组比较,SAP组血AMY和DAO水平均明显增高(P<0.05),小肠组织中SOD和GSH水平明显降低(P<0.05),MDA水平明显增高(P<0.05)。与SAP组比较,NAC+SAP组其6 h时间点血清AMY、DAO水平与SAP组同时间点无明显变化(P>0.05),而12、24 h时间点较SAP组同时间点显著降低(P<0.05);其小肠组织中MDA、SOD和GSH水平在6 h时间点与SAP组同时间点无明显差异(P>0.05),12、24 h时间点SOD和GSH水平明显增高(P<0.05),MDA水平明显降低(P<0.05)。结论:NAC通过增强肠组织抗氧化能力、维护肠组织内氧化还原平衡,可以保护肠黏膜结构和功能的完整性,对预防SAP大鼠肠屏障损害具有重要意义。

Experimental study of N-acetylcysteine on intestinal barrier in severe acute pancreatitis in rats

Objective ： To observe the protective effect of N-acetyleysteine （ NAC ） and its potential mechanism on the small intestinal mucosal barri- er in rats with severe acute pancreatitis （ SAP ）. Methods： Fifty-four healthy clean Wistar male rats were randomized into groups of sham oper- ation, SAP and NAC ＋ SAP （ n = 18 for each group） to develop the animal models. The animals were killed respectively at 6,12 and 24 h after model establishment, and the blood was obtained via abdominal aorta for deter- mining the levels of diamine oxidase （ DAO ） and amylase （AMY）. The tissues of terminal ileum and pancreas were taken for histopathological ex- amination. The small intestinal tissues were homogenized for determining the levels of malondialdehyde （ MDA）, glutathione （ GSH ） and superox- ide dismutase （SOD）. Results ： Significantly increased levels of AMY and DAO as well as MDA were seen in SAP group,yet SOD and GSH levels in the intestinal tissues were significantly decreased as compared with the Sham group（ P 〈 0.05 ）. Serum levels of AMY and DAO in NAC ＋ SAP group remained similarly at 6 h compared to the corresponding time point of SAP group（ P 〉 0.05 ） , whereas SOD and GSH levels at 12 and 24 h were increased greatly and MDA level was decreased significantly （P 〈 0.05 ）. Conclusion：NAC can be of great significance in protecting the small intestinal mucosal barrier of SAP rats from injury by enhancing the antioxygenic potential, maintaining the internal oxidative balance and in- tact intestinal structure and function.