不同营养支持途径对烧伤大鼠肠黏膜损伤和修复的影响

目的 探讨不同营养支持途径对大鼠烧伤后肠黏膜损伤和修复的影响及其可能的机制。方法 采用30％TBSAⅢ度烧伤大鼠模型，随机分成伤前对照组(C)，静脉营养组(PN)及肠道营养组(EN)。EN和PN组给予等氮、等热卡、等体积的营养液，观察肠组织中肠三叶因子(intestinal trefoil factor，ITF)含量、血浆二胺氧化酶(DAO)活性、肠黏膜跨膜电位差(PD)及增殖细胞核抗原(PCNA)的变化，并进行相关分析。结果 烧伤后肠黏膜组织结构受损，血浆DAO活性明显高于伤前，而PD、PCNA值及ITF含量均明显低于伤前。两组相比，EN组大鼠肠道受损程度明显低于PN组，同时其ITF含量、PD、PCNA值均高于PN组，而DAO活性显低于PN组。相关分析显示，ITF含量同血浆DAO活性呈显负相关，而与PCNA及PD值呈显正相关。结论 严重烧伤后肠黏膜结构受损与肠道合成和分泌ITF的能力大幅下降有关，肠道营养减轻伤后ITF的程度可能是在减轻肠黏膜损伤，促进肠黏膜修复方面优于静脉营养。

Effects of different nutritional support routes on the intestinal mucosa injury and repair in burned rats

Objective To compare the effects of different nutritional support routes on the intestinal mucosa injury and renovation in burned rats. Methods Wistar rats inflicted with 30% TBSA full thickness burns were employed as the model and randomly divided into three groups, namely burn with enteral nutrition (EN), burn with parenteral nutrition(PN), and normal control (C ). Solutions for both intravenous and oral administration were same in volume, calorie, nitrogen and other nutrients . The plasma diamine oxidase (DAO) activity, the intestinal mucosa change of proliferating cell nuclear antigen(PCNA), of transmembrane electric potential difference (PD), of intestinal trefoil factor(ITF) and their correlation analysis were observed. Results Plasma DAO activity increased obviously and PD,PCNA values,ITF content were much lower in EN,PN groups than those in C group. The ITF content, the values of PD and PCNA in EN were much higher than those in PN group, while DAO activity in EN group was obviously lower than that in PN group. In addition, ITF content was sighificantly negatively correlated to plasma DAO activity, and obviously positively correlated to PCNA and PD values. It was suggested that intestinal mucosa injury was much more severe in PN group than that in EN group. Conclusion Postburn intestine mucosal structural injury was related to the evident decrease of synthesis and secretion of ITF. Enteral nutrition might slow down the decrement of ITF, which could explain why EN was superior to PN in terms of decreasing intestinal mucosal injury and enhancing mucosal repair.