目的探讨骨髓来源的间充质干细胞(mesenchymal stem cells,MSCs)移植对野百合碱诱导的实验性肺动脉高压大鼠肺血管病变的干预作用。方法体外分离、培养并纯化SD大鼠骨髓MSCs。健康雄性SD大鼠随机分为3组,肺动脉高压组(n=20)、MSCs移植组(n=20):2组大鼠均一次性向背部皮下注射野百合碱50 mg/kg,诱导肺动脉高压动物模型;正常对照组(n=15):注射同体积的生理盐水。同等条件饲养3周后,MSCs移植组大鼠经舌下静脉注射5×106/ml的经Hoechst33342荧光染料标记的MSCs细胞悬液1 ml,肺动脉高压组和正常对照组大鼠注射等量L-DMEM液。移植后观察4周,测定3组大鼠生存率、肺动脉平均压、肺小动脉的微观结构的改变。结果肺动脉高压大鼠移植MSCs 4周后,生存率由30%上升到90%,肺动脉平均压由(42.7±2.3)mmHg下降到(24.7±2.3)mmHg,下降了50%;右心指数由(45.30±3.13)%下降到(37.90±3.18)%(q=29.86,P<0.01),肺小动脉病变得到有效改善。荧光显微镜观察到Hoechst 33342标记的MSCs在肺内定植且分化成大量新生血管并形成侧枝循环,肺动脉重构得到有效逆转。结论MSCs移植可有效减轻并逆转肺动脉重构的进程,其作用机制是MSCs分化形成新生血管,建立了侧枝循环,从而修复野百合碱诱导的肺血管损伤。 Objective To investigate the effects of bone marrow-derived mesenchymal stem cells (MSCs) transplantation on pulmonary vascular lesions induced by monocrotaline-induced pulmonary hypertension in rats. Methods The bone marrow MSCs of SD rats were isolated, cultured and purified. Healthy male Sprague-Dawley rats were randomly divided into 3 groups: pulmonary hypertension group (n = 20) and MSCs transplantation group (n = 20). Rats in both groups were injected monocrotaline 50 mg once daily subcutaneously into the back to induce pulmonary hypertension Animal model; normal control group (n = 15): injected with the same volume of saline. Under the same conditions for 3 weeks, MSCs transplantation group rats were injected subcutaneously with 5 × 106 / ml Hoechst33342 fluorescent dye-labeled MSCs cell suspension 1 ml, the pulmonary hypertension group and normal control group were injected with equal amount of L- DMEM solution. After 4 weeks of transplantation, the survival rate, mean pulmonary artery pressure, microstructure of pulmonary arterioles were measured. Results After 4 weeks MSCs transplantation, the survival rate increased from 30% to 90%. The mean pulmonary artery pressure decreased from (42.7 ± 2.3) mmHg to (24.7 ± 2.3) mmHg, down by 50% 45.30 ± 3.13)% to (37.90 ± 3.18)% (q = 29.86, P <0.01). Pulmonary arterioles were effectively improved. Fluorescence microscopy observed Hoechst 33342 labeled MSCs colonized in the lung and differentiated into a large number of neovascularization and the formation of collateral circulation, pulmonary artery reconstruction was effectively reversed. Conclusion MSCs transplantation can effectively alleviate and reverse the process of pulmonary artery remodeling. Its mechanism is that MSCs differentiate to form new blood vessels and establish collateral circulation to repair monocrotaline-induced pulmonary vascular injury.