Lp(a)与LDL氧化修饰的比较

脂蛋白（a）［Lp（a）］是一种特殊的血浆脂蛋白，其结构、理化性质和脂质组成与低密度脂蛋白（LDL）极为相似。氧化低密度脂蛋白（Ox－LDL）在动脉粥样硬化（AS）的发生、发展中起重要作用，Lp（a）的氧化亦发生于体内动脉壁。在体外，Lp（a）能经铜离子（Cu2＋）介导发生氧化修饰，但与LDL相比，Lp（a）氧化的延迟时间是LDL的1．62倍，氧化速率和氧化程度均只有LDL的63％，故Lp（a）对氧化的敏感性和氧化程度均较LDL为低，其高度致AS作用，难以完全用较高的氧化敏感性来加以解释。

Comparasion of Lp(a) and LDL Oxidative Modification

Lipoprotein(a) is a specific plasma lipoprotein that closely resembIes LDL in structure, physicaland chemical properties, and lipid compositions. Oxidation of LDL plays a pivotal roIe in foam cellformation; while Lp(a) oxidation also occurs in vivo in the arterial wall. In copper (E )-induced lipidperoxidation experiments in vitro, the lag-phase of Lp(a) was 1 .62 longer, while the propgagtionphase and total diene production were 63% lower than the corresponding LDL preparation from thesame blood donor. lt implies that the susceptiblity of Lp(a) for oxidation was lower than that ofLDL, and the postulated higher atherogenic properties of Lp(a) as compared to LDL might not bedirectly related to a higher sensitivity towards oxidative modifications.