LDL Particle Size by Gradient-Gel Electrophoresis Cannot Be Estimated by LDL-Cholesterol/Apolipoprotein B Ratios

Abstract

LDL particles have been shown to be heterogeneous in size, density, and composition. Heterogeneity of LDL particles with respect to size has been demonstrated by analytic ultracentrifugation (1), density-gradient ultracentrifugation, gradient-gel electrophoresis (GGE), high-performance gel-filtration chromatography, dynamic light scattering, and electron microscopy. Among these methods, GGE is the most reliable and widely used, but it has the drawback of being labor-intensive. Recently, the ratio of the LDL-cholesterol (LDL-chol) concentration to the LDL-apolipoprotein B (LDL-apo B) concentration has been used as an alternative index of hyperapobetalipoproteinemia and small dense LDL (2)(3)(4)(5). We therefore studied the relationship between LDL particle size as measured by GGE and as estimated by the LDL-chol/LDL-apo B ratio. LDL particle size was quantified by the above two methods in samples from healthy controls (n = 49) and from hyperlipemic subjects (n = 81). The …