【摘要】 目的　探讨氧化修饰低密度脂蛋白 (ox L DL)和天然低密度脂蛋白 (n LDL)促血管平滑肌细胞 (VSMC)增殖是否与细胞外基质(ECM)降解及粘附蛋白合成有关。方法　应用 Northern印迹和 3 H- Td R掺入的方法 ,观察两种脂蛋白对 VSMC表达基质金属蛋白酶 - 2 (MMP- 2 )和骨桥蛋白 (OPN)的影响 ,以及 ECM代谢与 VSMC增殖之间的关系。结果　 1 0 μg/ml ox L DL作用于细胞 2 4 h可使 MMP- 2和 OPN基因表达活性增加 1倍左右 ;n LDL对两种基因表达的诱导作用较弱 ,高浓度的 ox LDL对 MMP- 2和 OPN表达不产生明显的影响。在一定浓度和时间范围内 ,LDL促细胞增殖作用显示量 -效与时 -效依赖关系。结论　 ox LDL和 n L DL可在多位点上发挥促进 VSMC增殖和迁移的作用更多还原

【Abstract】 ? Objective To study whether or not the function of oxidized low density lipoprotein(oxLDL) in promoting vascular smooth muscle cell(VSMC) proliferation was concerned with the degradation of extracellular matrix(ECM) and the synthesis of adhesion protein.Methods Northern blot was used to analyze the effects of oxLDL or natural low density lipoprotein(nLDL) on matrix metalloproteinase 2 (MMP 2) and osteopontin(OPN) gene expression.The influence of DNA synthesis stimulated by oxLDL or nLDL was observed with 3 H TdR incorporation experiment.Results The expression activities of MMP 2 and OPN induced by 10 μg/ml oxLDL for 24h were two times compared with control cells.But no obvious effects were observed when the level of oxLDL was 50 μg/ml.At the same condition,the expressions of MMP 2 and OPN induced by nLDL was lower than those stimulated by oxLDL.The effects of LDL on VSMC proliferation were concentration and time dependent.Conclusions The change of MMP 2 and OPN gene expression was on the mechanisms by which oxLDL and nLDL stimulated VSMC proliferation and migration. 〔更多还原