Concentrations of apolipoproteins B, C-I, C-II, C-III and E in sera from normal men and their relation to serum lipoprotein levels.

The concentrations of apolipoproteins B, C-I, C-II, C-III and E (by enzyme immunoassay), and cholesterol, triglycerides and phospholipids both in while serum and in serum very low (VLDL), low (LDL) and high (HDL) density lipoproteins, HDL2 and HDL3, were determined in sera from 29 randomly selected normolipidemic men, age 40-60 years, in Stockholm, Mean values, +/- SD, were for, apolipoprotein B, 720 +/- 162; C-I, 63 +/- 14; C-II, 27 +/- 11; C-III, 125 +/- 57; and for E, 25 +/- 6 mg/l. A skewness to the right of the distributions was found for apolipoproteins B and C-II and for serum triglycerides and VLDL lipids. The relations between the different variables were studied by linear correlation analysis. Several significant correlations existed between the lipoprotein levels. Apolipoprotein C-I, C-II and C-III were significantly correlated with each other, whereas neither apolipoprotein B nor apolipoprotein E was correlated with any other apolipoprotein. The following significant, positive correlations existed between the apolipoproteins and total serum lipids and/or lipids of lipoprotein density classes: apolipoprotein B with serum cholesterol and LDL lipids, apolipoprotein C-I with HDL3 cholesterol, apolipoprotein C-II with serum triglycerides and VLDL lipids, apolipoprotein C-III with serum cholesterol and phospholipids. Apolipoprotein E showed no correlation with either serum lipids or lipoproteins.