Shen M M, Krauss R M, Lindgren F T, Forte T M
J Lipid Res. 1981 Feb;22(2):236-44.
Equilibrium density gradient ultracentrifugation of serum low density lipoprotein (LDL) from twelve healthy human subjects was used to separate six subfractions with mean density ranging from 1.0268 to 1.0597 g/ml. Mean corrected peak flotation rate (Sof) measured by analytic ultracentrifugation, and mean particle diameter determined by negative staining electron microscopy, both declined significantly with increasing density of the subfractions. Major differences in chemical composition of the subfractions were noted, including a significantly lower triglyceride content and higher ratio of cholesteryl ester to triglyceride in the middle fractions compared with those of highest and lowest density. Concentration of fraction 2 correlated positively with HDL (P less than 0.01) and negatively with VLDL (P less than 0.001); concentration of fraction 4 correlated negatively with HDL (P less than 0.05) and positively with VLDL (P less than 0.001) and IDL (P less than 0.01). LDL may thus include subspecies of differing structure and composition which might also have different metabolic and atherogenic roles.
采用平衡密度梯度超速离心法对12名健康受试者的血清低密度脂蛋白（LDL）进行分离，得到6个亚组分，其平均密度范围为1.0268至1.0597 g/ml。通过分析超速离心法测得的平均校正峰漂浮率（Sof）以及通过负染电子显微镜测定的平均颗粒直径，均随着亚组分密度的增加而显著下降。各亚组分的化学成分存在显著差异，其中中间密度亚组分的甘油三酯含量显著低于最高和最低密度亚组分，胆固醇酯与甘油三酯的比例则高于最高和最低密度亚组分。组分2的浓度与高密度脂蛋白（HDL）呈正相关（P<0.01），与极低密度脂蛋白（VLDL）呈负相关（P<0.001）；组分4的浓度与HDL呈负相关（P<0.05），与VLDL呈正相关（P<0.001），与中间密度脂蛋白（IDL）呈正相关（P<0.01）。因此，LDL可能包含结构和组成不同的亚类，这些亚类可能还具有不同的代谢和致动脉粥样硬化作用。
