兔动脉粥样硬化斑块内VSMCs凋亡与RANTES水平的相关性研究

Correlations between Expression of RANTES and Apoptosis of VSMCs in Atherosclerotic Rabbits

目的研究血浆和斑块局部受激活后调节性正常T细胞表达和分泌因子(regulated on activated normal T cellexpressed and secreted factor,RANTES)表达水平与兔动脉粥样硬化斑块内血管平滑肌细胞(vascular smooth musclecells,VSMCs)凋亡程度的相关性。方法 40只雄性家兔随机分为:①空白组(Blank组)和②对照组(Control组):均普通饲料喂养;③稳定斑块组(AS组)和④易损斑块组(VAP组):均高脂饮食。Control和VAP组给予药物触发(蝰蛇毒+组织胺),Blank和AS组给予生理盐水。测定各组血脂和血浆RANTES水平,Real time-PCR和Western blot检测主动脉RANTES转录和表达水平,TUNEL染色后计算各组斑块血管平滑肌细胞(VSMCs)凋亡率及其与RANTES水平的相关系数。结果高脂喂养组家兔血脂水平较普通喂养组明显升高(P<0.01)。VAP组RANTES表达水平和凋亡率明显高于AS组(P<0.01)、Control组(P<0.01)和Blank组(P<0.01);AS组明显高于Control组(P<0.01)和Blank组(P<0.01);但Blank组和Control组间差异无统计学意义(P>0.05)。各组VSMCs凋亡率与RANTES表达水平均呈正相关(均P<0.05)。结论 RANTES过表达可能通过加重斑块局部的炎症反应而诱导斑块内VSMCs凋亡。

Objective To study the correlations between the expression of regulated on activated normal T cell expressed and secreted factor（RANTES）and apoptosis of vascular smooth muscle cells（VSMCs）in atherosclerotic rabbits.Methods Forty male rabbits were divided into four groups randomly：（1）blank group（n=10）and control group（n=10）：receiving a standard diet for 16 weeks;（2）AS group（n=10）and VAP group（n=10）：receiving a high-cholesterol diet（1% cholesterol,5% lard in rabbit food）for 16 weeks.Blank and AS groups were triggered by Russel＇s viper venom（RVV）and histamine at 24 and 48 h before execution,and control and AS groups were administered the same dosage of sterile saline injection according to the above delivery time and location.Rabbits were euthanized at the 16th week,and blood lipid and plasma RANTES were measured in 0,16 weeks.The expression levels of RANTES mRNA and protein were detected by using real-time PCR and Western blot.The apoptosis rate of VSMCs in plaques was assayed by using TUNEL and its correlation coefficients with RANTES were measured.Results Blood lipid levels in high-cholesterol diet groups were higher than in standard diet groups（P〈0.01）.The levels of RANTES and apoptosis rate of VSMCs in AS and VAP groups were increased significantly as compared with those in blank and control groups（P〈0.01）.There was significant difference in RANTES expression and apoptosis rate between VAP and AS groups（P〈0.01）,but no between blank and control groups（P〉0.05）.Apoptosis of VSMCs was positively related with RANTES expression in all groups（P〈0.05）.Conclusion The overexpression of RANTES could induce the VAMCs apoptosis by aggravating the local inflammatory reaction in the atherosclerotic plaques.