受体细胞参与移植动脉内膜增生的研究

Involvement of recipient cells in neointimal hyperplasia in rat aortic allograft

目的研究大鼠移植动脉新生内膜细胞Sry基因的表达,探讨受体细胞在移植动脉内膜增生中的作用。方法建立大鼠腹主动脉移植模型,分为4组:雌雄同系移植组、雌性异系移植组、雄性异系移植组、雌雄异系移植组。移植术后10周时,取移植动脉标本,进行病理组织学观察,测量其内膜厚度和中膜厚度,分析移植动脉内膜增生情况;采用显微切割技术收集新生内膜细胞,用PCR方法检测Sty基因的表达,分析新生内膜细胞与受体细胞的关系。结果异系移植组移植动脉内膜显著增生,动脉壁内膜厚度及内膜／中膜厚度比均显著高于同系移植组(P<0．01); 而同性或异性异系移植组之间差异无统计学意义(P>0．05)。PCR分析显示,雄性异系移植组和雌雄异系移植组在242 bp处均有1条特异性扩增条带,而雌性异系移植组则无相应的核酸扩增条带。结论受体细胞作为移植物血管新生内膜细胞的来源,参与移植动脉内膜增生及移植物动脉硬化。

Objective To study the expression of Sry gene in neointimal cells in rat aortic allografts and investigate the role of recipient cells in neointimal hyperplasia of aortic allografts. Methods The aortic transplant model was established by means of micro-surgery in rats. The recipients were divided into 4 groups： female-male aortic isografts, female-female aortic allografts, male-male aortic aUografts, female-male aortic allografts. Ten weeks after transplantation, aortic grafts were removed at autopsy and processed for histological evaluation;and the neointimal thickness and neointimal/medial thickness （NIT/ MT） ratio were measured and analyzed statistically among groups. Neointiml cells were harvested from cryastat sections of aortic allografts by microdissection method. The Sty gene-specific PCR was performed on the genorne of neointimal cells to analyze the origin of neointimal cells involved in aortic allografts. Resuits Aortic allografts indicated significant neointima formation 10 weeks after transplantation. The neointimal thickness and NIT/MT ratio of aortic allografts were significantly increased in all of aortic allografts groups as compared with those in aortic isografts groups （ P 〈 0.01 ）, and there was no significant difference between aortic allografts groups. PCR assay revealed that a distinct DNA band with molecular weight of 242 bp emerged in the male-male aortic allografts group and female-male aortic allografts group respectively, but not in the female-female aortic allografts group. Conclusion As the origin of neointimal cells, recipient cells contribute to the pathological neointimal hyperplasia of aortic allograft and transplant arteriosclerosis.