摘要
目的探讨肠外和肠内营养对外科创伤应激大鼠肠上皮细胞紧密连接、屏障功能及微生态环境的影响。方法SD大鼠随机分成对照组、全肠外营养组(TPN)和普通肠内营养组(EN)。建立创伤应激模型,接受等氮、等能量营养支持后光镜和电镜下观察肠黏膜形态,比较肠道细菌脏器移位率、肠黏膜occludin蛋白免疫组化表达及肠道菌群数量等。结果电镜下TPN组肠上皮损伤程度较严重,而EN组损伤程度较轻,肠上皮紧密连接、微绒毛较完整;光镜下Chiu分级,TPN组和EN组比较差异有统计学意义(P<0.05)。EN组肠道跨膜结合蛋白表达优于TPN组(P<0.05)。EN组肝、肺和肠系膜淋巴结的肠道细菌移位率低于TPN组(P<0.05)。EN组肠道内乳酸杆菌和双歧杆菌数量均高于TPN组,但差异未达到统计学意义。结论肠内及标准肠外营养都不能完全维持创伤大鼠肠黏膜屏障不受损害及阻止肠道细菌移位,但肠内营养组肠黏膜屏障损害较轻,肠道细菌移位率低,且增加了肠上皮occludin蛋白表达,与肠外营养比较,有利于改善肠道屏障,从而减少细菌移位的可能。
Objective To compare the effects of enteral nutrition （EN） and parenteral nutrition （PN） on gut mucosal barrier function and intestinal epithelial tight junctions in rats after surgical stress. Methods Fifty SD rats with surgical trauma were randomly divided into three groups： total parenteral nutrition （TPN） group and enteral nutrition （EN） group with isocaloric and isonitrogenous nutrition and placebo group. Nutrients were administered via the neck vein and needle jejunostomy for the TPN group. The homogenated tissues of liver, lung, and mesenteric lymph nodes were cultured to determine the bacterial transloeations rates. The transmembrane binding proteins （occludin） were measured with immunohistochemistry. The ultrastructure and morphology of intestinal epithelial tight junctions were observed by electron microscope. The feces in cecum were cultured for anaerobic bacterial growth analyses. Results The EN group had more laetobacteria and bifydobacteria than the TPN group, but not statistical significant. The EN group had greater expression of occludin in the intestines than the TPN group. Furthermore, the intestinal epithelial tight junction and microvilli of the EN group were more intact compared with those of the TPN group. The bacterial translocations rates of liver, lung and mesenteric lymph nodes were significantly lower in the EN group than in the TPN group. Conclusion Neither EN nor standard PN maintains intestinal membrane barriers. But EN increases the expression of transmember binding proteins, maintains the gut epithelial tight junction, improves intestinal mucosal barrier and reduces gut bacterial transloeation.
出处
《四川大学学报（医学版）》
CAS
CSCD
北大核心
2009年第4期615-618,共4页
Journal of Sichuan University(Medical Sciences)
关键词
肠内营养
肠外营养
肠屏障功能
紧密连接
Enteral nutrition Parenteral nutrition Gut barrier function Tight junction
