肠道营养促进烧伤大鼠肠三叶因子表达的实验研究

目的 探讨肠道营养对烧伤大鼠三叶因子（ITF）及其mRNA表达的影响。方法 采用30％体表面积Ⅲ度烧伤大鼠模型，随机分成伤前对照（C）,静脉营养（PN）及肠道营养（EN）组。采用原位杂交、免疫组化和高效液相色谱等手段检测了烧伤后大鼠肠组织中肠三叶因子（ITF）ITF mRNA的变化，并观察了两组大鼠肠道受损情况。正常大鼠小肠中ITF及ITF mRNA均有一定表达，它们主要分布于肠绒毛杯状细胞中。烧伤后肠道组织结构受损，ITF mRNA表达明显降低，肠杯状细胞分泌ITF的能力大幅下降，特别是ITF二聚体的含量远远低于伤前（P＜0.01）。两组比较，尽管肠道营养不能逆转烧伤后ITF下降的趋势，但能明显抑制其下降幅度，同时EN组肠粘膜受损程度也明显低于PN组。结论 严重烧伤后肠粘膜结构受损的ITF合成下降的主要原因，与静脉营养相比肠道营养可减轻肠粘膜受损程度，降低ITF特别是ITF二聚体的下降幅度。

Experimental study on the improvement of intestinal trefoil factor expression by enteral nutrition in burned rats

Objective To explore the mechanism and effects of enteral nutrition on intestinal trefoil factor (ITF) as well as ITF mRNA expression in burned rats. Methods Wistar rats were inflicted with 30% total body surface area full thickness burns and randomly divided into three groups: burned and enteral nutrition (EN), burned and parenteral nutrition (PN), and normal control(C). The expression and content of ITF in intestine were determined with in situ hybridization (ISH), immunohistochemical technique and high performance liquid chromatography (HPLC). Results ITF and ITFm RNA were expressed in whole small intestine and mostly located in goblet cells of intestinal villus. After burn injury, the structure of intestinal mucosa was severely damaged and the ability of goblet cell to synthesize and secrete ITF, especially the content of ITF dimer were significantly decreased. EN could lessen the extent of ITF drop though it could not reverse this trend. Meanwhile, as compared with PN, EN could abate intestinal mucosa injury obviously. Conclusion There is a correlation between the declined ability of intestine synthesis and secretion of ITF and the damage of intestine structure postburn. EN is beneficial to minimizing intestine injury, promoting intestinal mucosa reparation, and abating ITF drop.