蛋白酶激活受体-2对动脉粥样硬化斑块发展和稳定性作用的实验研究

Effect of protease activated receptor-2 on the development and stability of atherosclerotic plaque

目的:探讨蛋白酶激活受体-2(PAR-2)对动脉粥样硬化斑块发展和稳定性的影响。方法:将32只6周龄雄性Apo E-/-小鼠随机分为对照组、实验组,每组16只。两组均给予高脂饮食建立动脉粥样硬化模型,连续喂养14周。实验组给予腹腔注射SLIGRL-NH2(5μmol·kg^(-1)·d^(-1)),对照组给予腹腔注射0.9%生理盐水,持续喂养至24周,处死小鼠并收集相关检测标本进行检测,采用酶法检测血浆总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)和低密度脂蛋白(LDL-C),采用免疫组化检测巨噬细胞表面分子抗-2(Mac-2)、α平滑肌激动蛋白(α-SMA)、血小板-内皮细胞粘附分子(CD-31)、基质金属蛋白酶-9(MMP-9)、基质金属蛋白酶-13(MMP-13)、血管细胞间粘附分子-1(VCAM-1),采用RT-PCR检测TNF-α、γ干扰素(IFN-γ)、IL-6、Egr-1、MCP-1等炎症因子mRNA表达。对比分析两组小鼠各项检测结果差异。结果:32只小鼠动脉粥样硬化模型建模成功率为93.75%(30/32),实验组小鼠PAR-2 mRNA表达明显高于对照组(P﹤0.05),两组小鼠血清TC、TG、LDL-C、HDL-C浓度及体质量(BW)差异无统计学意义(P﹥0.05),实验组小鼠动脉粥样硬化斑块纤维帽厚度小于对照组,斑块核心坏死率、Mac-2、α-SMA、CD-31、MMP-9、MMP-13、VCAM-1等检测结果明显高于对照组(P﹤0.05),实验组TNF-α、IFN-γ、IL-6、Egr-1、MCP-1等炎症因子mRNA表达相对水平明显高于对照组(P﹤0.05)。结论:PAR-2激动剂能通过激活PAR-2促进小鼠动脉粥样硬化斑块发生发展,加快斑块内的炎症反应。

AIM： To investigate the effect of protease activated receptor-2 on the development and stability of atheroselerotic plaque. METHODS： Thirty two six-week-old male ApoE-/- mice were randomly divided into experimental group and con- trol group, 16 rats in each. Both the two groups were given a high-fat diet for fourteen weeks to set up atherosclerosis model. The experimental group was given intraperitoneal injection of SLIGRL-NH2 （5 μmol · kg-1· d-l）, while the control group was given intraperitoneal injection of 0.9% saline. After the continuous feeding for 24 weeks, mice were kill- ed and the related testing samples were collected. Enzyme assay method was used to detect the total of cholesterol （ TC ）, triglyceride （ TG）, high density lipoprotein cholesterol （HDL-C） and low density lipoprotein （ LDL-C ）, immune-histochemical was used to detect Mac-2, α-SMA, CD-31, MMP-9, MMP-13, VCAM-1, and RT-PCR was used to detect TNF-α, IFN-γ, IL-6, Egr-1, MCP-1 and other in- flammatory cytokines mRNA expression. Results were compared between the two groups. RESULTS： Thirty two six-week-old male ApoE-/- mice were set up atherosclerosis model, the success rate of which was 93.75% （30/32）; the PAR-2 mRNA in the experimental group was significantly higher than that of the control group （ P 〈 O. 05 ） ; no statistical difference was observes in the two groups about ser- um TC, TG, LDL-C, HDL-C and BW concentration （ P 〉 0.05 ） ; the atheroselerotic plaque fibrous cap thickness of the experimental group is less than the control group; the plaque core necrosis rate, Mac-2, α-SMA, CD-31, MMP-9, MMP-13, VCAM-1 and other test results were significantly higher than those of the control group （ P 〈 0.05 ） ; TNF-α, IFN-γ, IL-6, Egr-1, MCP-1 and other inflammatory factors relative to the level of mRNA expression in the ex- perimental group were significantly higher than the control group （P 〈0. 05 ）. CONCLUSION ： PAR- 2 agonist can promote the development of atheroscle- rotic plaque in mice by activating PAR-2, and can accelerate the inflammatory reaction in the plaque.