HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Beghin, L. Articles by Luc, G. Search for Related Content PubMed PubMed Citation Articles by Beghin, L. Articles by Luc, G. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol. 41, 1172-1176, July 2000
Copyright © 2000 by Lipid Research, Inc.

Methods

Measurement of apolipoprotein B concentration in plasma lipoproteins by combining selective precipitation and mass spectrometry

Correspondence to: Gérald Luc

The measurement of apolipoprotein B (apoB) in purified lipoproteins by immunological assays is subject to criticism because of denatured epitopes or immunoreactivity differences between purified lipoproteins and standard. Chemical methods have therefore been developed, such as the selective precipitation of apoB followed by quantification of the precipitate. In this study, we present the measurement of apoB concentration in lipoproteins purified by ultracentrifugation by combining isopropanol precipitation and gas chromatography/mass spectrometry. Very low density lipoprotein (VLDL; d < 1.006 g/mL); VLDL plus intermediate density lipoprotein (VLDL + IDL; d < 1.019 g/mL); and VLDL, IDL, and low density lipoprotein (VLDL + IDL + LDL; d < 1.063 g/mL) were purified by ultracentrifugation. Apolipoprotein B-100 was selectively precipitated by isopropanol. The leucine content of the pellet was then determined by gas chromatography/mass spectrometry, using norleucine as internal standard. Knowledge of the number of leucine molecules in one apoB-100 molecule makes it possible to calculate the plasma concentration of apoB in the various lipoprotein fractions. ApoB in IDL (d 1.006–1.019 g/mL) and LDL (d 1.019–1.063 g/mL) were then determined by subtracting VLDL-apoB from apoB in lipoproteins d < 1.019 and apoB in lipoproteins d < 1.019 g/mL from apoB in lipoproteins d < 1.063 g/mL, respectively. The isopropanol precipitate was verified as pure apoB (>97%) in lipoprotein fractions isolated from normo- and hyperlipidemic plasma and the method appeared reproducible.

The combination of isopropanol precipitation and the GC/MS method appears therefore to be a precise and reliable method for kinetic and epidemiological studies.—Beghin, L., N. Duhal, P. Poulain, P. Hauw, B. Lacroix, J-M. Lecerf, J-P. Bonte, J-C. Fruchart, and G. Luc. Measurement of apolipoprotein B concentration in plasma lipoproteins by combining selective precipitation and mass spectrometry. J. Lipid Res. 2000. 41: 1172–1176.

Supplementary key words: apolipoprotein B, lipoproteins, mass spectrometry

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K. Bach-Ngohou, K. Ouguerram, R. Frenais, P. Maugere, B. Ripolles-Piquer, Y. Zair, M. Krempf, and J. M. Bard Influence of Atorvastatin on Apolipoprotein E and AI Kinetics in Patients with Type 2 Diabetes J. Pharmacol. Exp. Ther., October 1, 2005; 315(1): 363 - 369. [Abstract] [Full Text] [PDF]

				J. S. Millar, C. Maugeais, K. Ikewaki, D. M. Kolansky, P.H. R. Barrett, E. C. Budreck, R. C. Boston, N. Tada, S. Mochizuki, J. C. Defesche, et al. Complete Deficiency of the Low-Density Lipoprotein Receptor Is Associated With Increased Apolipoprotein B-100 Production Arterioscler. Thromb. Vasc. Biol., March 1, 2005; 25(3): 560 - 565. [Abstract] [Full Text] [PDF]

				K. Ouguerram, M. Chetiveaux, Y. Zair, P. Costet, M. Abifadel, M. Varret, C. Boileau, T. Magot, and M. Krempf Apolipoprotein B100 Metabolism in Autosomal-Dominant Hypercholesterolemia Related to Mutations in PCSK9 Arterioscler. Thromb. Vasc. Biol., August 1, 2004; 24(8): 1448 - 1453. [Abstract] [Full Text] [PDF]

				K. Ouguerram, T. Magot, Y. Zair, J. S. Marchini, B. Charbonnel, H. Laouenan, and M. Krempf Effect of Atorvastatin on Apolipoprotein B100 Containing Lipoprotein Metabolism in Type-2 Diabetes J. Pharmacol. Exp. Ther., July 1, 2003; 306(1): 332 - 337. [Abstract] [Full Text] [PDF]