血管黏附蛋白1在大鼠重症失血性休克中的表达

目的 观察重症失血性休克及复苏过程中大鼠小肠及血清中血管黏附蛋白1(VAP-1)的表达和活性变化,探讨抑制其功能对休克预后的影响.方法 将实验大鼠随机分为假手术组、休克组、休克复苏组、复苏对照组和复苏实验组,每组10只.建立重症失血性休克及复苏大鼠模型,采用蛋白质印迹和real-time RT-PCR法检测假手术组、休克组、休克复苏组休克前、休克1h、复苏1h时小肠组织中VAP-1表达及其编码基因含量,ELISA法检测血清中VAP-1含量及其活性.复苏实验组加用20 mg/kg 2-溴乙胺,复苏对照组加用1 mL/kg生理盐水,比较两组复苏后的血压、复苏24 h后小肠黏膜损伤情况(Chiu's评分)和小肠黏膜上皮细胞凋亡情况(TUNEL),并比较大鼠24 h生存率.结果 重症失血性休克组大鼠小肠组织VAP-1蛋白水平以及其编码基因mRNA水平、血清中VAP-1含量及其活性均较假手术组升高(均P＜0.05),复苏后上述各值均有所下降,但仍高于假手术组.相对于生理盐水对照组,休克复苏后1h和24 h使用20 mg/kg2-溴乙胺的复苏实验组大鼠血压升高(P值分别为0.010和0.039),且复苏实验组Chiu's评分及肠黏膜上皮细胞凋亡指数均低于生理盐水复苏对照组(P值分别为o.022和0.002),休克大鼠24 h生存率也高于复苏对照组(90％vs 60％).结论 重症失血性休克能使大鼠VAP-1的表达、活性增高,而液体复苏能减轻这种增高;抑制其活性能改善重症失血性休克及复苏后的低血压以及小肠黏膜的损伤和细胞凋亡,提高大鼠24 h生存率.

Expression of vascular adhesion protein-1 in severe hemorrhagic shock and resuscitation in rats

Objective To observe the expression and activity changes of vascular adhesion protein-1 (VAP-1) in the small intestine and serum of rats during severe hemorrhagic shock and resuscitation, and to study its influence on shock prognosis. Methods Fifty rats were evenly randomized into sham group, hemorrhagic shock group, shock resuscitation group, control recovery group and the experimental recovery group. Rat models of severe hemorrhagic shock and resuscitation were established. Before shock, 1 hour after shock and 1 hour after resuscitation, the expressions of VAP-1 protein and mRNA in the intestinal tissues of rats were examined by Western blotting analysis and real-time RT-PCR, respectively; and the serum levels of VAP-1 and its activities were determined by ELISA kit. Rats in the experimental recovery group was resuscitated by injection of 20 mg/kg 2-bromoethylamine and those in the control recovery group were given 1 mL/kg normal saline, and then the blood pressure, intestinal mucosa injury (Chiu's score), small intestinal epithelial cell apoptosis (TUNEL detection) and 24-hour survival rates were compared between the two recovery groups. Results The intestinal VAP-1 protein and mRNA expressions and the serum VAP-1 and its activities in the severe hemorrhagic shock group were significantly higher than those in the sham shock group (P<0.05). Compared with the shock group, the above parameters were decreased in the recovery group, but were still higher than those in the sham group. Compared with the saline control group, 20 mg/kg 2-bromoethylamine significantly increased the blood pressure of animals 1 h and 24 h after recovery (P=0.010, 0.039), significantly improved the Chiu's score and apoptosis index of small intestinal epithelial cells (P=0.022, P=0.002), and improved the 24-hour survival rates of rats(90% to 60%). Conclusion The levels of VAP-1 and its activities are increased in severe hemorrhagic shock rats, and fluid resuscitation can inhibit this increase. Inhibition of VAP-1 activities can improve the low blood pressure, intestinal mucosa injury and apoptosis of small intestinal mucosa cells after the severe hemorrhagic shock and resuscitation, improving the 24-hour survival rates of rats.