CRP、IL-6、TNF-α与移植物动脉硬化早期发病的关系

CRP,IL-6 and TNF-α in the pathogenesis of allograft arteriosclerosis in rats

目的探讨血清炎症因子与移植血管动脉硬化早期发病的关系。方法将36只同种异体胸主动脉腹腔移植大鼠分成4个实验组,每组9只。A组术后1周处死;B组术后2周处死;C组术后3周处死;D组术后4周处死。16只同系移植对照大鼠对应每个实验组,每次处死4只。术前及处死时抽血分离留取血清,采用酶联免疫吸附法检测C-反应蛋白(CRP)、白细胞介素6(IL-6)、肿瘤坏死因子(TNFα-)水平;处死后留取血管标本,HE染色观察血管病理改变,用免疫组织化学法检测血管外膜炎症细胞浸润及α-肌动蛋白(α-actin)、周期蛋白依赖性激酶1(CDK1)、增殖细胞核抗原(PCNA)在血管壁中的表达。对比各组与术前血清炎症因子水平变化及各组间观察指标的变化。结果CRP水平,各实验组及对照组均较术前基础水平明显增高(P<0.01),B、C、D实验组较对照组明显升高(P<0.01);IL-6水平,B实验组较术前升高(P<0.05),A、C、D实验组较术前明显升高(P<0.01),A、B、C对照组较术前基础水平升高(P<0.05),A、C、D实验组较对照组水平明显升高(P<0.01);TNF-a水平,A、B、C实验组较术前升高(P<0.05),D实验组较术前明显升高(P<0.01),各对照组与术前无明显变化,各实验组均较对照组明显增高(P<0.01)。术后7 d,外膜大量炎症细胞浸润;术后14 d,外膜有轻度胶原纤维增生伴炎症浸润;术后28 d,外膜明显增厚,内有大量增生的平滑肌细胞、胶原纤维及炎症细胞,血管中层断裂,可见外膜平滑肌细胞迁移至内膜,内膜亦出现明显纤维化及平滑肌细胞增生。在血管外膜平滑肌细胞中,α-actin、PCNA和CDK1表达逐渐升高(P<0.05),且早于内膜。结论大鼠同种异体胸主动脉腹腔移植后血清炎症介质水平呈持续升高,说明各种免疫因素导致外膜炎症反应,并参与移植血管动脉硬化的早期发病。

Objective To study the role of serum inflammatory factors and allograft adventitial inflammation in the pathogenesis of allograft arteriosclerosis in rots, Methods Thirty-six allograft rats and 16 within strain control rats were randomly divided into 4 groups （9 experimental rats and 4 controls） ： group A, sacrificed at the first post-operative week; group B, sacrificed at the second post-operative week; group C, sacrificed at the third post-operative week; and group D, sacrificed at the fourth post-operative week. Blood samples were collected before the transplantation operations and at the time of sacrifice. The method of Enzyme Linked Immunosorbent Assay was used for serum inflammatory factors （CRP, IL-6 and TNF-α）, HE staining for pathologie changes of aortic allograft and immunohistochemical method for adventitial inflammatory cell infiltration, α-actin, CDK1 and PCNA. The inflammatory factors and other observation results were compared between groups and the pre-operative groups. Results CRP level significantly increased in all control groups and experimental groups （P 〈 0.01） and of B, C and D experimental groups were higher than the controls （ P 〈 0.01 ）, IL-6 level increased in the experimental group B （ P 〈 0.05） and significantly increased in groups A, C and D （ P 〈 0.01） and in the control groups A, B and C （ P 〈 0.05）, but it was significant higher in the experimental groups than in the control groups （ P 〈 0. 01 ）. TNF-α level had no difference between the controls and the preoperative basal levels, all experimental groups had higher levels than the preoperative and control groups （ P 〈 0.01 ）. Adventitial inflammatory cell infiltration was foand in the allograft groups 7 days after the transplantation, mild adventitial collagen fiber proliferation accompanied by inflammatory infiltration was foand in the allograft groups 14 days after the transplantation, and significandy adventitial proliferation with smooth muscle cells, collagen fiber and inflammatory cells, intimal fibrous degeneration and smooth muscle cell proliferation were foand in the allograft groups 28 days after the transplantation. In allograft adventitial smooth muscle cells, the expressions of α-actin, PCNA and CDK1 were increased （P 〈 0.05） and preceded the expressions in intimal smooth muscle cells. Conclusion The serum inflammatory factor levels in thoracic aorta transplantation rats gradually increase, indicating that increased inflammatory factors and allograft adventitial inflammation resulting from immane or non-immune factors and adventitial SMC proliferation are both involved in the pathogenesis of early allograft arteriosclerosis.