低密度脂蛋白亚组份的组成和抗氧化性

The compositions and capacity of antioxidation of serum low density lipoproteins subfractionations

目的：观察低密度脂蛋白（ＬＤＬ，密度１．０２５～１．０５０ｍｇ／Ｌ）的组成和抗氧化性。方法：用超速离心提取正常人ＬＤＬ，再运用密度梯度离心将ＬＤＬ分成不同亚组份，并观察体外Ｃｕ２＋氧化ＬＤＬ不同亚组份氧化产物２３４ｎｍ处吸光度的变化（氧化曲线）。结果：密度越高的亚组份，电泳迁移率越快，甘油三酯（ＴＧ）／胆固醇（ＣＨ）比值越低。ＴＧ／ＣＨ比值越高的亚组份抗氧化修饰的能力越低。若在氧化体系中加入刺梨汁，能明显起到抗氧化作用。结论：抗氧化剂能提高ＬＤＬ抗氧化能力。

Objectives: To observe the compositions and capacity of antioxidation of serum low density lipoproteins subfractionations. Methods: We isolated LDL in d 1.024￣1.050 mg/L from normal serum by ultracentrifugation and divided it into several different subfractionations with density gradient ultracentrifugation. Oxidation could be induced in vitro by copper and be measured by continuously monitoring conjugated diene absorbaned at 234nm . Results: LDL sub fractionations had faster electrophoretic mobility and lower TG/CH ratio with the density increasing. The lag time of LDL oxidation was related to TG/CH ratio. Juice of rose roxburghiitratt as an antioxidant could delay lag time greatly. It was an effective anti oxidant of lipoprotein and had potentially applicable value in preventing atherosclerosis. Conclusions: The compositions of serum low density lipoproteins subfractionations is related to its capacity of antioxidation.