氧自由基在肝硬化门脉高压大鼠肠粘膜屏障损伤中的作用及别嘌呤醇的保护作用

Effects of Oxygen Radicals: on Gut Barrier Function of Chronic Portal Hypertensive Rats and Protective Role of Allopurinol

为探讨氧自由基在肝硬化门脉高压大鼠肠粘膜屏障中的作用及别嘌呤醇的保护作用 ,建立肝硬化门脉高压大鼠模型 ,分别检测正常对照组、肝硬化门脉高压组及治疗组中丙二醛 (MDA)、黄嘌呤氧化酶 (XO)以及细菌移位(BT) ,并观察肠粘膜形态学及超微结构的改变。结果显示 :正常对照组肠系膜淋巴结培养阳性率为 40 .0 % ,脾为13.3% ,门静脉和肝均为 0 .0 % ;肝硬化门脉高压组 ,肠系膜淋巴结培养阳性率为 5 0 .0 % ,脾、肝、门静脉分别为2 0 .0 %、40 .0 %、30 .0 % ;治疗组肠系膜淋巴结、脾、肝、门静脉培养阳性率依次为 45 .1%、18.2 %、18.2 %、0 .0 % ;3组细菌移位率分别为 11.5 %、35 .0 %、2 0 .4% ;空肠组织中MDA含量 (μmol/L) ,肝硬化门脉高压组高于治疗组和正常组 (P <0 .0 1) ;XO含量 (U/L) ,肝硬化门脉高压组高于治疗组和正常组 (P <0 .0 1)。提示氧自由基是导致肝硬化门脉高压大鼠肠粘膜屏障障碍的重要因素 ;别嘌呤醇抑制XO转化为氧自由基可以减轻肠粘膜屏障受损。

To explore the role of oxygen free radicals in gut barrier function of chronic portal hypertensiver (pH) rats and protective effect of allopurinol, the model of chronic portal hypertensive rats was established. The changes of malondial dehyde(MDA),xanthine oxidase (XO)and the positive incidence of enteral bacteria cultured from live mesenteric lymph nodes (MLN) blood samples were observed. Results showed that bacteria were found in the MLNs in 40.0%(6/15)in 13.3%(2/15)in spleen of normal group. The incidence of positive culture from the MLNs and spleen,liver and portal vein in chronic portal hypertension group (n=10)was 20.0%?40.0%?and 30.0% respectively. Finally.The MLNs spleen liver and portal vein in allopurinol treatment group(n=11)showed 45.1%,18.2%,18.2% and 0.0% of enteral bacteria positive rate. The incidence of BT showed 11.5%, 35.0% and 20.4% in three groups. Ileum tissure MDA levels (μmol/L) in cirrhotic group was significantly higher than those in nomal group (97.85±8.93 vs 45.27±6.84,P< 0.01 ).In the allopurinol groups; the level of MDA(49.84±1.84)was significantly lower than those in cirrhotic group (P< 0.01 ). XO activity (U/L) of the ileum mucosa in cirrhotic group was higher than those in normal group (156.83±10.08 vs 82.93±2.06,P< 0.01 ).Allopurinol significantly attenuated XO activity 78.23± 1.07 , P< 0.01 ).Results indicated that oxygen free radicals may be one of the primary causes for gut barrier function disturbance in pH. Allopurinols can attenueate the gut burrier function injury by inhibiting intestinal mucosal lipid peroxidation in pH.