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研究高密度脂蛋白（HDL）氧化修饰后对其结构及对低密度脂蛋白（LDL）氧化的影响。在体外用Cu2+氧化人血浆HDL，观察其蛋白和脂质部分的变化，并测定在HDL存在条件下LDL氧化的硫代巴比妥酸值（TBARS）。结果：氧化HDL（OX－HDL）的TBARS值升高，色氨酸残基（Trp）的特征荧光吸收（λ286，335nm）强度降低且λmax（发射）从335nm升至341nm，紫外吸收（λ234nm）增高，琼脂糖凝胶电泳迁移增快。LDL氧化后的TBARS值为13．40±0．42。在HDL或Ox－HDL（50μg和100μg）共存条件下，LDL氧化的TBARS值分别为6．24±0．71，1．43±0．04和12.75±0.47，12.58±0．23。结论：HDL氧化修饰后其脂质和蛋白部分均经历显著变化，HDL氧化导致其抑制LDL氧化能力的丧失。
To study the effect of high density lipoprotein (HDL) oxidative modification on its structure and its effect on the oxidation of low density lipoprotein (LDL). Human plasma HDL was oxidized with Cu2 + in vitro, changes in its protein and lipid fractions were observed, and LDL-oxidized thiobarbituric acid values (TBARS) were measured in the presence of HDL. Results: The TBARS values of oxidized HDL (OX-HDL) increased, the intensity of the characteristic fluorescence absorption (λ286,335nm) of tryptophan residues (Trp) decreased and the λmax (emission) increased from 335nm to 341nm, Increased, agarose gel electrophoresis migration faster. The TBARS after LDL oxidation was 13.40 ± 0.42. The LDL-oxidized TBARS values were 6.24 ± 0.71, 1.43 ± 0.04 and 12.75 ± 0.47, 12.58 ± 0.23, respectively, in the presence of HDL or Ox-HDL (50 μg and 100 μg). CONCLUSION: HDL oxidation undergoes significant changes in its lipid and protein fractions and HDL oxidation leads to its loss of ability to inhibit LDL oxidation.