急性肝衰竭大鼠肠黏膜屏障功能变化特点分析

摘要

Objective To explore the changes of gastrintestinal dysfunction in rats withacute liver failure (ALF) ,so to provide new idea for the treatment of ALF. Methods Total of 120 SD rats were divided into control group and model group randomly with 60 in each. The model group was made ALF model by hypodermic injection with thioacetamide ;and the control group was given same amount of saline. After model formation,4 mL blood was taken from every group at 24,36,48 hours to detect the changes of alanine aminotransferase( ALT) ,aspartate aminotransferase( AST) , total bilirubin (TBiL), intestinal fatty acid binding protein (iFABP) , endotoxin level, the bacterial translocation rates of mesenteric lymph nodes and portal vein ,and the pathological changes of ileum were also observed. Results Compared with the control group,the serum ALT,AST,TBil levels at 24,36,48 hours were increased obviously. The Pearson correlation analysis demonstrated positive correlation between the serum levels of iFABP and the damage liver function. Plasma endotoxin levels also increased significantly at early stage ( P < 0.01). The rates of bacterial translocation to mesenteric lymphnodes reached 30% at 48 h (P=0.013) and to portal vein reached 30% at 48 h (P = 0.013). Conclusion At the early stage after ALF,the level of iFABP and endotoxin may play an important role in the prediction of the gastrointestinal dysfunction.%目的 探讨急性肝衰竭(ALF)大鼠肠黏膜屏障功能变化特点,为ALF的诊治提供新思路.方法 将120只SD大鼠随机分为模型组及对照组各60只.模型组腹腔注射硫代乙酰胺复制ALF模型；对照组腹腔注射等量生理盐水.两组分别于制模后24、36、48 h取血检测血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、总胆红素(TBil)、肠脂肪酸结合蛋白(iFABP)、内毒素水平及肠系膜淋巴结和门静脉血细菌移位率,并观察回肠病理变化.结果 与对照组比较,模型组制模后24、36、48 h血清ALT、AST、TBil含量均明显升高；24、36 h血清iFABP水平明显升高(P ＜0.05或P＜0.01)；Pearson相关性分析显示,模型组血清iFABP水平与肝功能指标ALT、AST均呈显著正相关.早期内毒素水平有明显升高,48 h达到峰值(P＜0.01).肠系膜淋巴结细菌移位在制模24 h后明显升高,48 h达到30％ (P=0.013),门静脉血细菌移位48 h达到30％ (P =0.013).模型组回肠病理可见黏膜下充血、水肿、固层中性粒细胞浸润,部分绒毛尖端脱落.结论 ALF早期即可出现肠黏膜屏障功能受损,引发肠道细菌和内毒素移位；iFABP升高可能是ALF早期肠黏膜屏障功能受损的预警指标.