Very low density lipoproteins obtained from normolipidemic subjects were fractionated into subclasses by means of affinity chromatography on a heparin-Sepharose column in the presence of MnCl2. The four subfractions eluted at 0.05, 0.12, 0.20, and 0.38 M NaCl and they differed in chemical composition and apoprotein pattern. The relative amounts of apoB and apoE in subfractions increased with increasing concentrations of the NaCl eluant. Modification of the arginyl residues with 1-2 cyclohexadione demonstrated that arginine plays an important role in determining the elution pattern of VLDL. In vitro studies indicated that only fractions eluted at 0.2 and 0.5 M NaCl compete with LDL for cellular receptors. These data suggest that the various subfractions may represent VLDL at different stages of catabolism.