Hirano Tsutomu, Ito Yasuki, Koba Shinji, Toyoda Miwako, Ikejiri Ayako, Saegusa Haruhisa, Yamazaki Jun-ichi, Yoshino Gen
First Department of Internal Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan.
Arterioscler Thromb Vasc Biol. 2004 Mar;24(3):558-63. doi: 10.1161/01.ATV.0000117179.92263.08. Epub 2004 Jan 15.
Recently, we established a simple method for the quantification of small dense LDL cholesterol (C) using heparin-magnesium precipitation. The small dense LDL-C level was identical to cholesterol in the denser LDL fraction with a density of 1.044 to 1.063 g/mL. The aim of this study was to examine clinical significance of this precipitation method for small dense LDL-C.
Small dense LDL-C was measured by a direct homogenous LDL-C assay in the supernatant that remained after heparin-magnesium precipitation with density <1.044 lipoproteins. In 313 normolipidemic subjects, the mean value of small dense LDL-C was 31+/-13 mg/dL. In 462 healthy subjects, small dense LDL-C levels were positively correlated with serum triglyceride and LDL-C and were inversely correlated with high-density lipoprotein cholesterol (HDL-C). Combined hyperlipidemia showed the highest small dense LDL-C level among the various types of hyperlipidemia. Patients with type 2 diabetes had an increased small dense LDL-C level (55+/-17). Patients with coronary heart disease also had increased small dense LDL-C levels (53+/-30) irrespective of the presence of diabetes, whereas their LDL-C levels were comparable to those of normolipidemic controls (111+/-31 versus 104+/-22).
These results suggest that measurement of small dense LDL-C by the present precipitation method is useful to evaluate atherogenic risk and may be applicable to routine clinical examination.
最近，我们建立了一种使用肝素-镁沉淀法对小而密低密度脂蛋白胆固醇（C）进行定量的简单方法。小而密低密度脂蛋白-C水平与密度为1.044至1.063 g/mL的更致密低密度脂蛋白组分中的胆固醇相同。本研究的目的是检验这种小而密低密度脂蛋白-C沉淀法的临床意义。
通过直接匀相低密度脂蛋白-C测定法测量肝素-镁沉淀后上清液中的小而密低密度脂蛋白-C，该上清液中脂蛋白密度<1.044。在313名血脂正常的受试者中，小而密低密度脂蛋白-C的平均值为31±13 mg/dL。在462名健康受试者中，小而密低密度脂蛋白-C水平与血清甘油三酯和低密度脂蛋白-C呈正相关，与高密度脂蛋白胆固醇（HDL-C）呈负相关。在各种类型的高脂血症中，混合性高脂血症的小而密低密度脂蛋白-C水平最高。2型糖尿病患者的小而密低密度脂蛋白-C水平升高（55±17）。冠心病患者的小而密低密度脂蛋白-C水平也升高（53±30），无论是否患有糖尿病，而他们的低密度脂蛋白-C水平与血脂正常对照组相当（111±31对104±22）。
这些结果表明，用目前的沉淀法测量小而密低密度脂蛋白-C有助于评估动脉粥样硬化风险，可能适用于常规临床检查。
