实验性慢性缺氧与肺血管结构的重建

目的：主要研究慢性缺氧与肺血管结构重建的关系，利用常压缺氧舱建立大鼠缺氧性肺动脉高压模型。实验动物分为3组：缺氧3天组、7天组、14天组。通过免疫组化的方法检测一氧化氮合成酶(NOS)的表达和含量，部分标本通过电镜观察。结果：在缺氧过程中，肺血管的胶原纤维明显增生，超微结构观察显示血管在早期可见内皮细胞损伤并伴有血小板性血栓形成；到后期出现肌纤维母细胞和胶原纤维增生。实验显示随缺氧时间的延长内皮细胞NOS的含量逐渐升高，而肺血管内源性的舒张反应反而降低，管腔狭窄，血流阻力加大。文中讨论了慢性缺氧与肺血管结构重建的关系，肺缺氧性肺动脉高压的机理，内皮细胞形态及功能的改变在肺动脉高压形成中的意义。

Experimental chronic hypoxia and remodeling of the pulmonary blood vessel

To observe the relation between chronic hypoxia and remodeling of pulmonary blood vessel through establishing the rat chronically hypoxic pulmonary hypertension models in the hypoxic chamber. The experimental male Sprague-Dawley rats were divided into 3 groups:3 days, 7 days and 14 days after hypoxia. The expression and activity of nitric oxide synthetase (NOS) in endothelial cells of small artery were examined by immunohistochemical method and partial tissues were observed under electron microscope. The pulmonary arteries of rats were also observed under light microscope with HE and VG staining. Results: TBIn the development of chronic hypoxia,the collagen hyperplasia of vascular wall was obviously. The ultrastructural changes of the endothelial cells accompanied with formation of platelet thrombi were found in the early stage of injury. In the late stage proliferation of myofibroblast and collagen fibers appeared. The mechanism of chronic hypoxia pulmonary hypertension and the significance of the functional and morphological changes in endothelial cells during the formation of pulmonary hypertension was discussed.