Plasma high density lipoprotein subfractions in subjects with different coronary risk indices as assessed by plasma lipoprotein concentrations

Abstract

The distribution of plasma high density lipoprotein (HDL) subfractions was determined in 2 groups of healthy male subjects with different coronary risk indices (CI) as assessed by the ratio of total plasma cholesterol/HDL-cholesterol. The subjects in the 2 groups were of similar age and fitness (as assessed by VO 2max) The higher risk group (CI > 4.0) contained a lower relative concentration of a specific HDL subfraction, HDL 2b, separated by gradient gel electrophoresis, and a lower level of an apo E-rich HDL fraction, isolated by affinity chromatography, than the lower risk group (CI < 4.0). The concentration of total HDL-cholesterol was higher in the lower risk group due to a difference in HDL 2-cholesterol when separation was achieved by polyanion precipitation, but not when separation was made by ultracentrifugation. These observations suggest that the level of these specific HDL subfractions might, when taken in conjunction with plasma cholesterol concentration, provide a better index of coronary risk than that of total HDL as conventionally employed.