Objective: To investigate pulmonary vascular remodeling in rat model of pulmonary hypertension in left heart disease (PH-LHD). Methods: A total of 66 male minor Sprague-Dawley (SD) rats were randomly divided into control group (n=6), sham operation group (n=6) and model group (n=54). The rats in the control group entered the experimental procedure immediately without any treatment, and the rats in the sham operation group entered the experimental procedure 64 days after sham operation, and the rats in model group entered the experimental procedure (6 rats each) on day 1, day 3, day 5, day 8, day 15, day 22, day 36, day 50 and day 64 respectively after supracoronary aortic banding successfully. The lung tissue was fixed and cut and made into pathological sections to observe the characteristics of pulmonary vascular remodeling. Results: Medial thickening was mainly observed in pulmonary arterioles with diameter <100 μm [(11.17±1.03)%]. Additionally, medial thickening was seen in pulmonary arterioles with diameter 50-100 μm and 20-50 μm from day 15 [(12.73±1.15)%] and day 50 [(14.53±1.53)%], respectively. Medial muscularize of pulmonary arterioles were mainly observed in arterioles with diameter 20-50 μm, and deteriorated with time. Reduced pulmonary arteriole lumen size were observed with diameter 20-50 μm since day 50 (P<0.05). Conclusion: Pulmonary arteries with diameter >100 μm have little effect on the reconstruction of pulmonary vessels in PH-LHD rat model. However, arterioles with diameter 20-50 μm and 50-100 μm are the most important vessels involved in the formation of pulmonary hypertension, especially 20-50 μm.
目的： 探讨左心疾病所致的肺动脉高压(PH-LHD)大鼠模型中肺血管的重构特点。 方法： 选取66只雄性未成年Sprague-Dawley(SD)大鼠，随机分为对照组(6只)、假手术组(6只)和模型组(54只)，对照组大鼠未做任何处理，当天即进入实验程序；假手术组大鼠行假手术后64 d进入实验程序；模型组大鼠通过实施升主动脉缩窄手术来制备PH-LHD模型，造模成功后分别在术后第1、3、5、8、15、22、36、50、64天进入实验程序。行肺组织的固定和切取并制作成病理切片，观察肺血管重构的特点。 结果： 直径>100 μm的肺肌型动脉未观察到血管中层的增厚[第64天血管中层厚度与血管外径比值(11.17±1.03)%]。血管中层的增厚主要发生在肺细动脉，其中直径为50～100 μm的肺细动脉出现较早[第15天开始，(12.73±1.15)%]，而直径为20～50 μm的肺细动脉出现较晚[第50天开始，(14.53±1.53)%]。血管肌化主要是以直径为20～50 μm的肺细动脉为主，时间越长血管肌化程度越高；直径为20～50 μm的肺细动脉从第50天开始出现血管腔面积减小(P<0.05)。 结论： 在PH-LHD大鼠模型中的肺血管重构过程中，直径>100 μm的肺肌型动脉对肺动脉高压形成影响较小，20～50 μm和50～100 μm的肺细血管是参与肺动脉高压形成的主要血管，尤其是20～50 μm的肺细血管最为重要。.
Keywords: Hypertension, pulmonary; Pulmonary vascular remodeling; Rats.