实验性兔动脉粥样硬化病变中TRAIL、DR5的表达及意义

目的：探讨肿瘤坏死因子相关细胞凋亡诱导配体(TRAIL)通过死亡受体-5（DR5）途径诱导的细胞凋亡与动脉粥样硬化（AS）的关系。方法：采用球囊拉伤腹主动脉加高胆固醇饮食的实验方法，建立兔AS模型；血管超声检查明确腹主动脉斑块的形成情况，然后取静脉血和腹主动脉组织，用酶联免疫吸附试验（ELISA）检测AS组及正常组兔血清中可溶性TRAIL(sTRAIL)和可溶性DR5 (sDR5)的浓度，免疫组化染色检测AS组及正常组腹主动脉壁TRAIL和DR5的蛋白表达。并比较两组间各项参数的差异。结果：AS组兔血清中sDR5浓度显著高于正常组（P＜0.05），而两组兔血清中sTRAIL浓度差异无统计学意义（P＞0.05）。AS组兔腹主动脉的TRAIL、DR5蛋白表达强度显著高于正常组（P＜0.05），染色呈棕褐色,粗颗粒状，群集于中膜、脂质沉积处和斑块纤维帽处，高倍镜下,棕褐色颗粒主要分布在胞浆和胞核内；正常组兔腹主动脉内膜、中膜也有少量TRAIL、DR5表达，染色呈浅棕色，颗粒细小，分布散在。结论：TRAIL通过死亡受体途径诱导的细胞凋亡对AS的发生和发展起一定的促进作用，TRAIL及其受体DR5可能是AS的重要影响因子。

Expression and significance of TNF-related apoptosis inducing ligand and death receptor-5 in atherosclerosis rabbits

Objective: To explore whether TNF-related apoptosis inducing ligand(TRAIL)and death receptor-5(DR5) take part in the occurrence and development of atherosclerosis(AS).Methods: Twenty rabbits were randomly distributed into two groups: the control group and the atherosclerotic group.The experimental atherosclerotic models were made by endothelial injury on the ventro-aorta with a balloon and hyperlipid feeding lasting 12 weeks.The levels of sTRAIL and sDR5 in the serum were determined by enzyme linked immunoabsorbent assay(ELISA).The proteinum expression of TRAIL and DR5 in the ventro-aortas was detected by immunohistochemical technique.Results: In the course of research,2 rabbits died.The survival rate was 90%.Till the end of the research,the serum sDR5 in the AS group was more significantly elevated than that in control group(P<0.05),while the serum sTRAIL in two groups had no significant differences(P>0.05).The expressions of TRAIL and DR5 in the ventro-aortas in the AS group were significantly elevated than those in the control group(P<0.05).Conclusion: This study suggests that TRAIL and DR5 could promote the occurrence and development of AS.TRAIL and DR5 may be important factors for AS.