一氧化碳对缺氧性肺血管结构重建大鼠肺动脉转移生长因子表达的影响

目的探讨一氧化碳对缺氧性肺血管结构重建大鼠肺动脉中转移生长因子（TGF）表达的影响。方法将大鼠随机分为3组：常氧组（n=20）、低氧组（n=20）和低氧＋血红素加氧酶组（低氧＋HO组）（n=20）。以光学显微镜观测3组大鼠肺中型动脉及小型动脉的相对中膜厚度（RMT）。应用TGF的单克隆抗体经免疫组织化学技术对3组大鼠肺动脉TGF进行定位及半定量分析。结果低氧组大鼠中型肺动脉及小型肺动脉RMT均高于常氧组和低氧＋HO组（P〈0．01）。3组大鼠各级肺动脉内皮细胞中均有TGF的表达．低氧组高于常氧组和低氧＋HO组（P〈0．01）。中型肺动脉内皮细胞中TGF的表达与相应中型肺动脉RMT之间呈正相关（r为0．7835，P〈0．01）；小型肺动脉内皮细胞中TGF的表达与相应的小型肺动脉RMT之间呈正相关（r为0．8125，P〈0．01）。结论一氧化碳对缺氧性肺血管结构重建大鼠肺动脉中TGF表达有抑制作用。

Expression in pulmonary arteries of rats with hypoxic pulmonary vascular remodeling

Objective To investigate the impact of transforming growth factor(TGF) in the mechanisms by which carbon monoxide(CO) regulates hypoxic pulmonary vascular remodeling.Methods 60 rats were randomly divided into three groups: normoxic(n=20),hypoxic(n=20) and hypoxic+heme oxygenase(hypoxic+HO,n=20).The relative medial thickness(RMT) of small and medium muscularized pulmonary arteries were determined under light microscope.Immunohistochemical technique was used to assess the abundance and localization of TGF in pulmonary arteries.Results RMT of small and medium pulmonary arteries in rats of hypoxic group was markedly higher than that of normoxic group and hypoxic+HO group(P<0.01).TGF was expressed in pulmonary artery smooth muscle cells of three groups,more marked in hypoxic group than in normoxic group and hypoxic+HO group(P<0.01).There was a positive correlation between RMT and TGF expression in medium and small pulmonary arteries(r=0.7835 and 0.8125,P<0.01 respectively).Conclusion Carbon monoxide inhibited TGF expression by pulmonary arteries of rats with hypoxic pulmonary vascular remodeling.