中文摘要：

目的：探讨阿司匹林对脂多糖（LPS）诱导RAW264.7细胞中基质金属蛋白酶-9（matrix metalloproteinase-9, MMP-9）的表达及其机制研究。方法： MTT法检测LPS诱导RAW264.7细胞作用下，阿司匹林对细胞毒性的影响。Q-RT-PCR检测MMP-9 mRNA表达，免疫蛋白印迹法（western blot）检测MMP-9、p38MAPK及磷酸化p38（Phospho-p38,P-p38）蛋白表达。特异性抑制剂SB203580（SB）阻断p38MAPK通路后,分别应用Q-RT-PCR和Western blot检测MMP-9的基因和蛋白表达。结果： 阿司匹林呈剂量依赖性抑制MMP-9基因和蛋白表达。与LPS组相比，阿司匹林可明显抑制P-p38MAPK蛋白的表达，而p38MAPK总蛋白无明显变化。抑制p38MAPK通路后，MMP-9 mRNA和蛋白水平均明显下调。结论：阿司匹林抑制LPS诱导RAW264.7细胞中MMP-9表达可能与抑制p38MAPK信号转导通路有关，进而发挥其抗AS药理作用。

英文摘要：

AIM ： To investigate the effect of as- pirin on the expression of MMP-9 and its mechanism in LPS-induced RAW264. 7 ceils. METHODS： The cytotoxic effect of aspirin on LPS-induced RAW264.7 cells was detected by MTT assay. MMP- 9mRNA expression was detected by quantitative real-time PCR. The protein expression level of MMP-9, p38MAPK and Phospho-p38 （ P-p38 ） were exam- ined by western blotting. After the inhibition of p38MAPK pathway by specific inhibitor SB203580, the gene and protein expression of MMP-9 was meas- ured by Quantitative real-time PCR and western blot-ting separately. RESULTS：The gene and protein expression of MMP-9 were inhibited by aspirin in dose-dependent manner. The protein expression of P- p38 was significantly inhibited by aspirin as com- pared with LPS treatment group. However, the pro- tein expression of p38MAPK was not significantly different. The expression of MMP-9mRNA and pro- tein were p38MAPK obviously decreased after inhibiting pathway. CONCLUSION ： The results suggest that aspirin has potent anti-atherosclerotic action with inhibitory action on MMP-9 production by blocking p38MAPK pathway in LPS-induced RAW264.7 cells.