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目的:探索在野百合碱诱导的肺动脉高压大鼠模型中,实施经胸肺动脉去神经支配术改善肺动脉高压和肺动脉重构的效果.方法:将24只健康雄性Sprague Dawley(SD)大鼠按1:1:1比例随机分为对照组、假手术组及手术组.假手术组和手术组予一次性皮下注射野百合碱(60mg/kg),4周后采用右心导管测量三组大鼠平均肺动脉压等血流动力学参数.造模成功后,手术组行经胸肺动脉去神经支配术,假手术组仅开胸,术后2周后再采用右心导管测量各组大鼠平均肺动脉压等血流动力学参数,之后取心肺组织通过免疫组化、免疫荧光等方法观察其显微形态学变化.用右心室心肌细胞横截面积和右心室肥厚指数(RVHI)来衡量右心室肥厚程度.结果:野百合碱注射4周后,与对照组相比,手术组及假手术组的平均肺动脉压均显著升高(P均＜0.01),表明肺动脉高压大鼠造模成功;经胸肺动脉去神经支配术后,与假手术组相比,手术组大鼠的平均肺动脉压显著下降(P＜0.01),而且手术组肺小动脉中层壁厚占外径的百分比显著减少(P＜0.01),右心室心肌细胞横截面积及RVHI显著减少(P＜0.01).结论:经胸肺动脉去神经支配术可降低野百合碱诱导的肺动脉高压大鼠的平均肺动脉压,减少肺小动脉中膜肥厚,并减轻其右心室肥厚程度.“,”Objectives:The aim of this study was to observe whether transthoracic pulmonary artery denervation (TPADN) could reduce the pulmonary arterial pressure and attenuate pulmonary vascular remodeling in rats with pulmonary arterial hypertension induced by monocrotaline. Methods:Twenty-four healthy male SD rats were randomly divided into control group, sham operation group and operation group (n=8 per group). Rats in sham operation group and operation group received single subcutaneous injection of monocrotaline (MCT, 60 mg/kg). After four weeks, the mean pulmonary arterial pressure (mPAP) and other hemodynamic parameters were measured with the right heart catheter in rats of these two groups. Then, operation group received the surgery of TPADN, which included thoracotomy in left 2-3 rib, exposing pulmonary artery, and removing the near connective tissue of the pulmonary artery trunk. After two weeks of operation, the mPAP and other hemodynamic parameters were measured again by the right heart catheter. The microstructure changes of the heart and pulmonary vessels was observed by immunohistochemistry and immunofluorescence. Meanwhile, RV cardiomyocyte cross-sectional area (CSA) and the right hearthy pertrophy index (RVHI= RV/[LV+S]) were used to evaluate the degree of right ventricular hypertrophy. Results:After four weeks of injection of MCT, the mPAP was significantly higher in the operation group and the sham operation group than in control group (P＜0.01). Two weeks after the surgery of TPADN, the mPAP was significantly reduced in the operation group than compared in the sham group(P＜0.01). Meanwhile, the percentage of medial thickness to outer diameter of the small pulmonary arterioles, right ventricular myocardial cell cross-sectional area and RVHI were also significantly decreased in the operation group compared to sham operation group(all P＜0.01). Conclusions:Our results show that TPADN could reduce the mean pulmonary arterial pressure and attenuate the hypertrophy of medial thickness of small pulmonary arterioles and of right ventricle in PAH rats induced by monocrotaline.