急性肠系膜缺血模型的制作与实验研究及缺血修饰蛋白对肠缺血临床诊断的初步探讨

发布时间：2018-12-21 07:42

【摘要】：背景目的：急性肠系膜缺血早期诊断困难，致死致残率极高。近年来发病率有增高的趋势。有关于AMI的基础研究多是在以血管结扎为基础的动物模型上进行的。动脉结扎的模型只能模拟AMI的极端情况。急性肠系膜上静脉血栓形成则较静脉结扎的差别更大。研究模型不能代表临床发病的病理生理过程必然导致研究结果的偏差。现已有较多的关于激光导致血管狭窄甚至闭塞的报道。本实验拟采用激光直接照射肠系膜血管的方式致急性肠系膜血管狭窄，获得急性肠系膜缺血的模型，并观察模型中血清学标记物的变化。材料与方法：以实验大鼠开腹游离肠系膜动静脉后采用不同的激光参数分别照射动、静脉，缝合关腹观察。24小时后再次开腹观察，与肠系膜动静脉结扎的动物比较，探索导致急性肠系膜缺血的激光参数。找出理想的激光参数后取SD大鼠66只，随机分为11组，每组均为6只。C0、C1、C2组为对照组，分别在开腹游离肠系膜血管后即刻、1小时和2小时留取血液和肠管标本。A1、A2、T1组照射动脉；V1、V2、P1、P2、T2组为照射静脉。A1、V1组照射后1小时留取血液和肠管标本；A2、V2组于2小时留取血液和肠管标本；T1、T2组照射血管后15分钟内给予尾静脉内注射尿激酶，于2小时留取血液和肠管标本；P1、P2组照射静脉后于1小时、2小时取肠系膜上静脉血液标本。结果：以适当的激光参数直接照射肠系膜血管可以造成大鼠急性肠系膜缺血损伤模型，，不同的激光参数可以导致不同程度的肠缺血。模型中各组血清D二聚体有升高趋势，但与对照组相比没有统计学差异。体循环血液和门静脉内血液D二聚体水平相近，无统计学差别。肠型脂肪酸结合蛋白的含量在照射动脉或静脉后2小时均明显升高，与对照组相比有统计学差异。溶栓治疗对模型组动物的血清学指标和病理学表现无保护作用。缺血修饰白蛋白在大鼠模型各组之间无统计学差别；在临床肠系膜缺血病例（共10例）中阳性率为100%。缺血修饰蛋白在肠系膜缺血病人中比急性心肌梗死病人升高的幅度更高，具有统计学差别。结论：激光直接照射可形成急性肠系膜缺血的大鼠模型，急性肠系膜缺血时血清D二聚体升高，但无统计学差别；体循环血液标本D二聚体浓度与门静脉血液一致。肠型脂肪酸结合蛋白在2小时时明显升高，提示对诊断急性肠系膜缺血有意义。缺血修饰蛋白在动物模型中无变化，但是在临床病例中阳性率高。
[Abstract]:Background: early diagnosis of acute mesenteric ischemia is difficult and the rate of death and disability is very high. The incidence of disease has been increasing in recent years. Basic research on AMI is mostly done on animal models based on vascular ligation. The model of artery ligation can only simulate the extreme case of AMI. Acute superior mesenteric venous thrombosis is more different than that of venous ligation. The research model can not represent the pathophysiological process of clinical pathogenesis, which inevitably leads to the deviation of the research results. There have been more reports of laser-induced stenosis or occlusion of blood vessels. In this experiment, the acute mesenteric vessel stenosis was induced by direct laser irradiation to mesenteric vessels, and the model of acute mesenteric ischemia was obtained, and the changes of serological markers in the model were observed. Materials and methods: different laser parameters were used to irradiate the arteries and veins of the free mesenteric arteries and veins of the experimental rats, and to suture the closed abdomen for observation. After 24 hours, the rats were observed again, and compared with the animals with mesenteric arteriovenous ligation, and the results were compared with those of the animals with mesenteric arteriovenous ligation. To explore the laser parameters leading to acute mesenteric ischemia. After finding out the ideal laser parameters, 66 SD rats were randomly divided into 11 groups (6 rats in each group). Group A _ 2T _ 1 irradiated artery; The blood and intestinal specimens were collected 1 hour after irradiation in A1V1 group, and those in A2V2 group were retained at 2 hours after irradiation. Urokinase was injected into caudal vein within 15 minutes after irradiation in T _ 1T _ 2 group, blood and intestinal specimens were collected at 2 hours, and blood samples of superior mesenteric vein were collected at 1 hour and 2 hours after irradiation in P _ 1 / P _ 2 group. Results: rat models of acute mesenteric ischemia injury could be induced by direct irradiation of mesenteric vessels with appropriate laser parameters, and different laser parameters could lead to different degrees of intestinal ischemia. In the model, serum D dimer tended to increase, but there was no statistical difference compared with the control group. The level of D dimer in blood of systemic circulation and portal vein was similar, but there was no statistical difference. The content of intestinal fatty acid binding protein increased significantly at 2 hours after irradiation of artery or vein, which was significantly different from that of control group. Thrombolytic therapy had no protective effect on the serological indexes and pathological manifestations of the model group. The positive rate of ischemia modified albumin was 100 in 10 cases of mesenteric ischemia. Ischemic modified proteins were significantly higher in patients with mesenteric ischemia than in patients with acute myocardial infarction. Conclusion: the rat model of acute mesenteric ischemia can be established by direct laser irradiation. The serum D dimer level is increased in acute mesenteric ischemia, but there is no statistical difference, and the concentration of D dimer in blood samples of systemic circulation is consistent with that of portal vein blood. Intestinal fatty acid binding protein increased significantly at 2 hours, suggesting that it is of significance in the diagnosis of acute mesenteric ischemia. Ischemic modified protein did not change in animal model, but the positive rate was high in clinical cases.
【学位授予单位】：中国人民解放军医学院
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R572.3

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