大鼠肝肺综合征模型的建立

发布时间：2018-06-12 16:20

本文选题：肝肺综合症 + 一氧化氮　；参考：《浙江大学》2008年硕士论文

【摘要】： 背景: 呼吸系统症状在失代偿期肝病患者中是非常常见的,半数以上的患者有气短的主诉。在过去的10多年里,肝硬化患者肺血管异常越来越受到重视,因为人们意识到这是影响肝移植患者生存率的重要临床因素。当肺内血管扩张影响到动脉氧合时就可认为存在肝肺综合征(hepatopulmonary syndrome,HPS),15%-20%接受肝移植评估的患者合并有HPS,HPS的存在增加肝硬化患者的死亡率并可进一步加重门脉高压。经典的HPS定义为原发肝病、低氧血症和肺内血管扩张的三联征。肺内血管异常扩张是肝肺综合症的基本病理变化,对伴有低氧血症的严重肝病患者作尸检可以发现肺毛细血管弥漫性扩张,直径从正常的8μm-15μm扩张至20μm-50μm,甚至500μm。目前认为这种血管扩张的原因是肝功能损伤时血管扩张因子和收缩因子之间的失衡所致。由于肝功能障碍时肝脏灭活能力下降,加之门体分流的存在使扩血管物质直接进入肺循环,从而导致肺内扩血管物质的增多;同时缩血管物质含量下降、活性降低,或者肺血管内皮对血管收缩因子的敏感性降低,使原本关闭的无功能肺毛细血管前交通支开放,从而导致本来正常的低氧性肺血管收缩功能发生障碍。常见的血管活性物质有:一氧化氮、内皮素、一氧化碳、肿瘤坏死因子等,这些物质对HPS的发生、发展起重要的作用。大鼠慢性胆管结扎(chronic bile duct ligation,CBDL)是目前复制人HPS病理生理特征的唯一模型,与其他常用的肝硬化或门脉高压动物模型(如硫代乙酰胺、门脉部分结扎方法)相比,后者不伴有HPS形成。目的: 大鼠慢性胆管结扎(CBDL)是目前复制人HPS病理生理特征的唯一模型。本实验的目的就是研究大鼠肝肺综合征模型的建立及其病理生理演变过程,进一步阐明肝肺综合征的发病机制,为肝肺综合征的治疗提供新的理论基础和治疗切入点。方法: 采用Sprague-Dawley大鼠,慢性胆管结扎(CBDL)方法制备HPS动物模型,共36只,随机分为假手术组(Sham),2周组(2wk)和5周组(5wk)。采用病理染色观察肝硬化形成及肺血管扩张情况,血气分析检测动脉血氧分压从而验证造模情况。应用比色法检测血浆及肺组织中一氧化氮(NO),应用ELISA法检测血浆及肺组织中内皮素-1(ET-1)及肿瘤坏死因子-α(TNF-α)水平。统计学处理用EXCEL软件完成,计量资料数据表示方式以平均值±标准差(Mean±SD),两组计量资料采用非独立样本t检验。P＜0.05为差异有统计学显著性意义。结果: 病理观察显示CBDL 2wk时肝纤维化形成,5wk时肝硬化形成,肺血管随时间变化逐渐扩张。血气分析显示CBDL 2wk组和5wk组肺泡.动脉氧分压差与假手术组相比均有显著升高,证明通过CBDL成功复制了HPS模型。CBDL组血浆及肺组织中NO、ET-1含量均升高,与假手术组比较有显著性差异。CBDL组血浆中TNF-α含量升高,与假手术组比较有显著性差异。结论: CBDL大鼠可较好的复制HPS模型用于实验研究。血浆及肺组织中NO、ET-1及TNF-α水平增加可能HPS重要的发病机制之一。
[Abstract]:Background:
Respiratory symptoms are very common in patients with decompensated liver disease, and more than half of the patients have shortness of breath. Over the past 10 years, pulmonary vascular abnormalities in patients with cirrhosis are becoming more and more important, because people realize that this is an important clinical factor affecting the survival rate of patients with liver transplantation. Hepatopulmonary syndrome (HPS) is considered to exist when oxygen is combined. The patients with 15%-20% for liver transplantation are combined with HPS. The presence of HPS increases the mortality of the patients with cirrhosis and further aggravates the portal hypertension. The classic HPS is defined as the triple sign of primary liver disease, hypoxemia, and pulmonary vasodilatation.
Abnormal expansion of the blood vessels in the lungs is the basic pathological change of the hepatopulmonary syndrome. The diffuse expansion of the pulmonary capillaries can be found in patients with severe liver disease accompanied by hypoxemia. The diameter of the pulmonary capillary dilates from normal 8 UU M-15 to 20 m-50 mu m, or even 500 mu m.. The reason for this vascular expansion is the vasodilator factor at the time of liver function injury. Due to the imbalance between the contractile factors, the decrease of liver inactivation ability and the presence of portal body diffluence make the vasodilator directly enter the pulmonary circulation, which leads to the increase of the pulmonary vasodilator material, and the decrease in the content of the vasoconstrictor material, the decrease of the activity, or the sensitivity of the pulmonary vascular endothelium to the vasoconstrictor. Decrease, make the previously closed non functional pulmonary capillaries open, which leads to normal hypoxic pulmonary vasoconstrictor dysfunction. The common vasoactive substances are nitric oxide, endothelin, carbon monoxide, tumor necrosis factor and so on. These substances play an important role in the development of HPS.
Chronic bile duct ligation (chronic bile duct ligation, CBDL) is the only model that replicating the pathophysiological characteristics of human HPS at present. Compared with other commonly used liver cirrhosis or portal hypertensive animal models (such as thioacetamide and partial ligature of portal vein), the latter is not accompanied by HPS formation.
Objective:
Chronic bile duct ligation (CBDL) is the only model that replicating the pathophysiological characteristics of human HPS. The aim of this experiment is to study the establishment of rat hepato lung syndrome model and its pathophysiological evolution process, further elucidate the pathogenesis of Hepato lung syndrome, and provide a new theoretical basis and treatment entry point for the treatment of Hepato lung syndrome.
Method:
HPS animal models were prepared by Sprague-Dawley rats and chronic bile duct ligation (CBDL). A total of 36 animals were randomly divided into sham operation group (Sham), 2 weeks group (2wk) and 5 week group (5wk). Pathological staining was used to observe the formation of liver cirrhosis and pulmonary vasodilatation. Blood gas analysis was used to test arterial oxygen pressure to verify the model condition. Plasma colorimetric assay was used to detect plasma. And nitric oxide (NO) in lung tissue, the levels of endothelin -1 (ET-1) and tumor necrosis factor - alpha (TNF- alpha) in plasma and lung tissue were detected by ELISA.
The statistical treatment was completed by EXCEL software, and the data representation of the measurement data was mean standard deviation (Mean + SD). The two groups of measurement data were statistically significant with the non independent sample t test.P < 0.05.
Result:
Pathological observation showed the formation of liver fibrosis in CBDL 2wk, the formation of liver cirrhosis in 5wk, and the gradual expansion of the pulmonary vessels with time. The blood gas analysis showed that the CBDL 2wk group and the 5wk group had a significant increase in the difference of oxygen pressure from the sham operation group. It was proved that the NO of the plasma and lung tissue of the HPS model.CBDL group was successfully copied through CBDL, and the ET-1 content was increased. There was a significant difference between the sham operation group and the sham operation group. The plasma level of TNF- alpha in group.CBDL was higher than that in sham operation group.
Conclusion:
CBDL rats can better replicate the HPS model for experimental study. The increase of NO, ET-1 and TNF- alpha levels in plasma and lung tissue may be one of the important pathogenesis of HPS.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2008
【分类号】：R563;R-332

【共引文献】