添加谷氨酰胺的肠内营养对大鼠重症

目的 探讨肠内营养中联合应用谷氨酰胺(glutamine,Gln)对试验性大鼠重症急性胰腺炎(severe acute pancreatitis, SAP)肠黏膜细胞凋亡及凋亡调控基因Bax蛋白表达的影响.方法 雄性SD大鼠89只,随机分成对照组,SAP PN(肠外营养)组,SAP EN(肠内营养)组,SAP EN Gln,各组又分为4 d喂养组和7 d喂养组.分别在第4天、第7天剖杀大鼠检测各组各项指标.脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TdT-mediated dUTP Nick-End labeling,TUNEL)法检测肠黏膜上皮凋亡,免疫组化法检测小肠组织中Bax蛋白的表达.结果 凋亡指数(apoptosis index,AI)比较,各SAP组高于对照组(P<0.01);SAP EN Gln7 d组显著低于SAP EN、SAP PN7 d组(P<0.05);SAP EN Gln、SAP EN7 d组与各自4 d组相比,均显著降低(P<0.01).Bax蛋白阳性表达率EN Gln7天组明显低于其余各SAP组(P<0.05).结论 肠内营养中联合应用谷氨酰胺可通过抑制肠黏膜上皮细胞的凋亡,维持肠黏膜屏障的完整性,从而防止重症急性胰腺炎的细菌易位和继发感染.

Effects of glutamine in enteral nutrition on apoptosis of intestinal mucosal cells in rats with severe acute pancreatitis

Objective To study the effects of glutamine (Gln) in enteral nutrition(EN) on apoptosis and the expression of apoptosis-regulated genes Bax in rats with experimental severe acute pancreatisis(SAP).Methods Eighty-nine Sprague-Dawley rats were randomly assigned into control group,SAP parenteral nutrition(PN) group,SAP EN group and SAP EN Gln group.Each group was divided into four-day and seven-day subgroups again.Each index was tested on the 4th day or the 7th day.Apoptosis of mucosal cells were detected by TUNEL method,and the expressions of Bax protein were determined by SP immunohistochemistry.Results The apoptotic indexes(AI) of mucosal cells in SAP model groups were significantly higher than those in control group(P<0.01),and the results on the 7 th day in SAP PN and SAP EN groups were significantly higher than that in SAP EN Gln group(P<0.05).AI detected on the 7th day were also significantly lower than those detected on the 4th day in SAP EN and SAP EN Gln group(P<0.01).The positive rate of Bax protein expression in 7day-Gln EN group was significantly lower than that in EN and PN group(P<0.01).Conclusion Using glutamine in enteral nutrition maybe helpful to keep the integrity of gut barrier to decrease apoptosis of the epithelial cells and therefore to prevent gut bacterial translocation and following infection in severe acute pancreatitis.