硫化氢供体对低氧大鼠肺动脉平滑肌细胞小窝蛋白的影响

Effect of hydrogen sulfide donor on caveolin-1 expression in pulmonary artery smooth muscle cells from hypoxic rats

目的探讨硫化氢供体硫氢化钠（NariS）对低氧大鼠肺动脉平滑肌细胞小窝蛋白1（Cav-1）的影响。方法采用间断常压低氧法建立低氧大鼠模型。利用混合气体培养法制备大鼠低氧肺动脉平滑肌细胞模型。将32只SD大鼠随机分为4组（每组8只）：常氧组、低氧组、常氧＋NaHS组和低氧＋NariS组。免疫组织化学方法检测肺小动脉中膜厚度、肌化及增殖程度。采用荧光探针法检测活性氧（ROS）含量。蛋白免疫印迹法检测Cav-1的表达。结果低氧组大鼠右心室收缩压、右心室质量指数、肺小动脉中膜厚度、肌化及平滑肌增殖程度明显增加；低氧组大鼠肺动脉平滑肌细胞ROS产生增加及Cav-1表达降低；NaHS给予大鼠可改善肺动脉血流，缓解肺动脉中膜增厚，抑制肺动脉平滑肌细胞增殖，减少肺动脉平滑肌细胞ROS产生及增加Cav-1表达。结论NariS可通过降低低氧大鼠肺动脉平滑肌细胞ROS产生，上调Cav-1表达，抑制肺动脉平滑肌细胞增殖，缓解肺动脉重构。

Objective To determine the effect of hydrogen sulfide donor, sodium hydrosulfide （NariS）, on caveolin-1 （Cav-1） expression in pulmonary artery smooth muscle cells from hypoxic rats. Methods The chronic hypoxic rat model was established by intermittent normobaric hypoxia exposure. The hypoxic rat pulmonary artery smooth muscle cells （PASMCs） were cultured under mixed gas conditions. Thirty-two Sprague-Dawley （SD） rats were randomly and equally divided into four groups （normoxia group, hypoxia group, normoxia ＋ NariS group and hypoxia ＋ NariS group）. The pulmonary arteriole intima-media thickness, muscularization and PASMCs proliferation was measured by immunohistochemical assay. Reactive oxygen species （ROS） was assessed by fluorescent probe assays. Western blotting was used to detect the protein expression of Cav-1. Results Compared with control rats, right ventricular systolic pressure （RVSP）, right ventricular mass index （RVMI）, medial wall thickness, fully muscularized vessels and proliferation of PASMCs were significantly enhanced in response to hypoxia. The level of ROS was significantly higher and the expression of Cav-1 was decreased in the PASMCs of hypoxia group than in control groups. NariS treatment resulted in improvement of pulmonary arterial blood flow, alleviation of medial wall thickness, inhibition of PASMCs proliferation, decrease of ROS production, and enhancement of Cav-1 protein expression. Conclusion Naris treatment alleviates pulmonary vascular structural remodeling in chronic hypoxic rats by decreasing ROS production, up-regulating the expression of Cav-1, and inhibiting PASMCs proliferation.