Composition of HDL-2 and HDL-3 in familial hyperalphalipoproteinemia.

The content and percent composition of cholesterol, triglyceride, phospholipids, and total proteins in HDL-2 and HDL-3 were quantitated in 5 women with familial hyperalphalipoproteinemia to determine if there are any distinctive characteristics of the high density lipoproteins in this heritable disorder. The 5 women with familial hyperalphalipoproteinemia (FHA) were compared to 4 normal women, with the groups being comparable in regards to age (40 +/- 3 and 37 +/- 5 years), total plasma cholesterol (202 +/- 9 and 188 +/- 16 mg/100 ml), triglyceride (75 +/- 12 and 95 +/- 19), and differing in levels of high density lipoprotein cholesterol (C-HDL, 84 +/- 6 and 61 +/- 3 mg/100 ml) respectively. Total cholesterol in the HDL-2 and HDL-3 fractions obtained by ultracentrifugation were 43.2 +/- 3.3 and 33.8 +/- 4.1 in FHA subjects, higher than total cholesterol in HDL-2 and HDL-3 in normals, 25.8 +/- 6.2 and 21.5 +/- 1.3 mg/100 ml, P less than 0.025. Total concentration of HDL-3 was higher in FHA than in normal subjects, respectively 222.4 +/- 22.6 and 149 +/- 7.2 mg/100 ml, P less than 0.025. Lipid-protein percent composition of HDL-2 and HDL-3 in FHA and normals was nearly identical, and polyacrylamide gel electrophoresis revealed no qualitative differences in band migration and appearance of the HDL-2 and HDL-3 fractions in normal and FHA subjects. In these women with FHA, there appears to be an increased concentration of normal HDL-2 and HDL-3.