血小板转化生长因子与移植心脏血管病和纤维化关系的研究

目的 探讨血小板转化生长因子(PDGF)与移植心脏排斥反应之间的关系.方法 建立大鼠颈部心脏移植的动物模型.采用供体脾细胞(SPC)和环磷酰胺(CP)以及环孢素A(CsA)治疗移植受体,在移植术后的不同时间,采集移植心脏,对移植心脏血管病和心肌纤维化以及PDGF的表达水平等进行分析.结果 急性排斥反应和CsA治疗的移植组中,冠状动脉的外膜和中层有大量胶原纤维浸润,并有内膜的水肿、血管壁增厚和血管腔狭窄,PDGF在冠状血管和心脏组织中呈高水平表达.SPC和CP预处理后,移植心脏的存活时间明显延长,PDGF在冠状血管和心肌组织中呈低水平表达,移植心脏血管病和心肌纤维化明显减轻.结论 PDGF的表达水平与移植心脏血管病和心肌纤维化的严重程度密切相关,测定移植受体的PDGF水平可以预测移植器官的功能状况,为移植排斥反应的早期诊断和预防提供依据.

The effect of platelet-derived growth factor in rat cardiac allograft vasculopathy and myofibrosis

Objective To investigate the relationship between platelet-derived growth factor (PDGF) expression and the devel- opment of cardiac allograft rejection. Methods Heterotopic cervical heart ransplantation models were established. The recipients were treated with CsA and inoculation of donor splenocytes (SPC) followed by cyclophesphamide(CP). The cardiac grafts were har- vested at various stages after transplantation. The allografts were studied for vaaculopathy, myofibrosis and the expression of PDGF. Results Allografts collected from Group C demonstrated the abundant infiltration of collagenous fibers in the middle and outer layers of the coronary arteries. The edema and proliferation of intima as well as stenesis of lumen were revealed in group A and C. Addition- ally, immunohistological staining demonstrated high level expression of PDGF protein in cardiac muscle and coronary artery in group A and C. In contrast, pre-treatemnt of animals with SIC and CP induced long-term cardiac allograft survival. Importantly, the expres- sion of PDGF in cardiac muscle and artery in group B and D were significantly lower than in group A and C. The cardiac allograft vas- culopathy and paronchymal fibrosis in cardiac allograft were dramatically reduced in group B and D when compared with group A and C. Conclusion The expression level of PDGF is associated with the occurrence and development of allograft rejection and has positive correlation with the severity of cardiac allogrsft vaaculopathy and myofihrosis.