硫化氢抑制低氧性肺动脉高压大鼠肺动脉弹力蛋白的表达

目的　探讨硫化氢 (H2 S)抑制低氧性肺动脉高压(HPH)大鼠肺动脉弹力蛋白表达的变化。方法　将Wistar大鼠 2 4只随机分为 :对照组 (n =8) ,低氧组 (n =8) ,低氧 +硫氢化纳 (NaHS)组 (n =8) ,以右心导管测定 3组大鼠肺动脉平均压 (mPAP) ,分离右心室 (RV)和左心室加室间隔 (LV+S) ,计算RV/LV +S比值 ,并以光学显微镜观测肺血管结构变化 ,用免疫组织化学方法研究弹力蛋白和转化生长因子β(TGF β)在肺动脉平滑肌细胞的表达含量。 结果　低氧组的mPAP和RV/ (LV +S)比值明显高于对照组 (P均 <0 0 1) ,低氧 +NaHS组的mPAP和RV/ (LV +S)比值 ,明显低于低氧组 (P均 <0 0 1) ;低氧组肌型动脉、部分肌型动脉百分比明显高于对照组 (P <0 0 5 ,P <0 0 1) ,非肌型动脉百分比明显低于对照组 (P <0 0 1) ,低氧 +NaHS组肌型、部分肌型动脉百分比明显低于低氧组 (P均 <0 0 1) ,非肌型动脉百分比明显高于低氧组 (P <0 0 1) ;低氧组肺中、小型肺动脉平滑肌细胞弹力蛋白表达含量明显高于对照组 (P均 <0 0 1) ,低氧 +NaHS组肺中、小型肺动脉平滑肌细胞弹力蛋白表达含量明显低于低氧组 (P均 <0 0 1) ;低氧组肺中、小型肺动脉平滑肌细胞TGF β表达含量明显高于对照组 (P均 <0 0 1) ,低氧 +NaHS组肺中、小型肺动脉平滑

Hydrogen sulfide inhibited expression of elastin in pulmonary arteries of hypoxic pulmonary hypertensive rats

Aim To investigate the inhibitory effect of hydrogen sulfide on expression of elastin in hypoxic pulmonary hypertensive (HPH) rats. Methods Twenty-four rats were randomly divided into three groups:control group (n=8), hypoxic group (n=8) and hypoxia+NaHS group (n=8). Pulmonary artery mean pressure (mPAP) of three group rats was measured via right ventricular catheterization. Right ventricle and left ventricle+septum of each rats were isolated from intact rats and weight of right ventricle/(weight of left ventricle+septum) ratio was calculated. The percentage of muscularized arteries of small pulmonary arteries was measured using a light microscope. The expression of elastin and TGF-β in pulmonary artery smooth muscle cells was observed with immunohistochemistry. Results mPAP and weight of right ventricle/(weight of left ventricle+septum) ratio were significantly higher in rats of hypoxic group than those of control group (P<0.01) and they were much lower in rats of hypoxia+NaHS group than those of hypoxic group (P<0.01). The percentage of muscularized arteries and partly muscularized arteries of small pulmonary arteries was increased in rats of hypoxic group compared with that of control group (P<0.05,P<0.01) while the percentage of unmuscularized arteries to small pulmonary arteries was decreased in rats of hypoxic group compared with that of control group (P<0.01). However,when NaHS was used, the percentage of muscularized arteries and partly muscularized arteries of small pulmonary arteries was decreased in rats of hypoxic+NaHS group compared with that of hypoxic group (P<0.01). And the percentage of unmuscularized arteries to small pulmonary arteries was increased in rats of hypoxic+NaHS group compared with that of hypoxia group (P<0.01).The expression of elastin of median and small pulmonary artery smooth muscle cells in hypoxic group significantly increased compared with that in control group (P<0.01 ). While, it was decreased in rats of hypoxia+NaHS group compared with that of hypoxic group (P<0.01 ).The expression of TGF-β of median and small pulmonary artery smooth muscle cells in hypoxic group significantly increased compared with that in control group (P<0.01). While, it was decreased in rats of hypoxia+NaHS group compared with that of hypoxic group(P<0.01). Conclusion The result of this study showed that hydrogen sulfide might play a modulatory role on hypoxic pulmonary vascular structural remodeling and the development of HPH through inhibiting the expression of elastin of extracelluar matrix from hypoxic rats.