目的探讨肾上腺髓质素(ADM)对高肺血流性肺动脉高压大鼠肺血管结构重构的干预作用。方法 6周龄雄性SD大鼠21只,随机分为3组:对照组、分流组和分流+ADM组,每组大鼠各7只。对分流组和分流+ADM组大鼠行腹主动脉-下腔静脉分流术。对照组大鼠仅开腹暴露腹主动脉及下腔静脉,不做分流手术。8周后,对分流+ADM组大鼠,皮下埋置微量渗透泵,持续予ADM(1.5μg.kg-1.h-1)。2周后,采用右心导管法测定各组大鼠肺动脉压力,称重,并测定右心室/(左心室+室间隔)比值[RV/(LV+SP)],观察其肺动脉显微和超微结构的变化。结果与对照组比较,分流组大鼠肺动脉收缩压、肺动脉舒张压和肺动脉平均压均明显升高(Pa<0.01),RV/(LV+SP)比值明显增加(P<0.01),肺小血管肌化程度及中、小型肺动脉相对中膜厚度和相对中膜面积均明显增加(Pa<0.01),肺动脉超微结构发生明显改变,内皮细胞肿胀,内弹力层粗细不均甚至断裂,平滑肌细胞肥大,不同程度向合成表型转化。分流+ADM组与分流组比较,肺动脉压力和RV/(LV+SP)明显降低(Pa<0.01),肺动脉显微和超微结构改变明显缓解。结论通过微量渗透泵持续予ADM,能缓解大鼠高肺血流性肺动脉高压和肺血管结构重构的形成。 Objective To investigate the effects of adrenomedullin (ADM) on pulmonary vascular remodeling in rats with pulmonary hypertension. Methods Sixty-six male Sprague-Dawley rats were randomly divided into three groups: control group, shunt group and shunt + ADM group, with 7 rats in each group. Abdominal aorta-inferior vena cava shunt was performed on shunt and shunt + ADM rats. Rats in the control group were exposed only to the abdominal aorta and inferior vena cava without shunt surgery. After 8 weeks, the rats in shunt + ADM group were subcutaneously implanted with micro-osmotic pump, and ADM (1.5μg.kg-1.h-1) was continued. Two weeks later, the right pulmonary artery was used to measure the pulmonary arterial pressure, and the right ventricular / (left ventricular + interventricular septum) ratio [RV / (LV + SP)] was measured. Microstructure changes. Results Compared with the control group, the pulmonary artery systolic pressure, pulmonary diastolic pressure and pulmonary artery mean pressure in the shunt group were significantly increased (Pa <0.01), the ratio of RV / (LV + SP) was significantly increased (P <0.01) (P <0.01). The ultrastructure of pulmonary arteries changed obviously. The swelling of endothelial cells, the uneven thickness of the internal elastic layer and even the rupture of the smooth muscle cells , To varying degrees, the synthesis of phenotypes. Pulmonary artery pressure and RV / (LV + SP) were significantly decreased (P <0.01) in shunt + ADM group compared with shunt group, and pulmonary artery microstructure and ultrastructure were significantly relieved. Conclusion The continuous infusion of ADM through the micro-osmotic pump can relieve the pulmonary hypertension and pulmonary vascular remodeling in rats.