缺氧大鼠肺内动脉壁FN及LN的改变

目的　利用大鼠常压缺氧模型 ,采用形态计量学方法 ,系统观察缺氧大鼠肺动脉壁FN及LN的改变 ,进一步探讨缺氧性肺血管组织重建的机制。　方法　利用常压缺氧舱建立大鼠缺氧模型 ,取肺分别进行免疫组织化学染色和电镜观察。　结果　缺氧后肺动脉壁上FN及LN均增加 ,这一变化在缺氧 7d时最明显 ,且FN增加的程度及含量远远高于LN。电镜观察显示 ,肺动脉中膜平滑肌细胞有由收缩表型转化为合成表型的倾向。　结论　肺动脉壁上FN及LN增加 ,不仅可以增加血管紧张性及血管壁厚度 ,同时也为诱导中膜平滑肌细胞表型转换及增生提供了条件

THE CHANGES OF FN AND LN IN PULMONARY ARTERY OF HYPOXIC RATS

Objective In order to investigate the mechanism of the remodeling of pulmonary vascular in hypoxic pulmonary hypertension,normobaric hypoxic rat model (FIO 2=10%)was used to observe the changes of fibronectin(FN)and leminin(LN)within the pulmonary artery by morphological methods. Methods The normobaric hypoxic chamber was used to establish the hypoxic rat model. The lungs were taken off and stained with immunohistochemical method.Some specimens were examined by electromicroscopy. Results Immunohistochemical analysis revealed progressive increase in the deposition of FN and LN,which was most prominent in hypoxia 7d group.The content of FN was higher than LN.Electromicroscope revealed that the SMC of tunia media had transitted from a contractile to a synthetic phenotype. Conclusion Long term hypoxic exposure resulted in increasing of FN and LN in the wall of pulmonary artery.These increase not only raise the tension and make thickening of the vessels themselves,but also provide an environment for the transition of SMC from a contractile to a synthetic phenotype.FN and LN played an important role in the remodeling of pulmonary vascular directly and indirectly.