Evaluation of HDL2 and HDL3 cholesterol by a precipitation procedure in a normal population and in different hyperlipidemic phenotypes.

Gidez et al described a double precipitation method with polyanions to separate high density lipoprotein (HDL) subfractions, using sodium heparin to precipitate very low density lipoprotein (VLDL) and low density lipoprotein (LDL) first, and dextran sulphate 15000 to precipitate HDL2 from total HDL afterwards. This method has shown a very good correlation with the data from the analytical and preparative ultracentrifuge. The aim of this work is to use this method to analyse HDL2 and HLD3 levels in a population living in our district. We studied 163 subjects considered as 'normal' on the basis of anamnestic and clinical evaluation and routine analysis and 47 subjects with familial hyperlipoproteinemia (types IIa, IIb, and IV). The results obtained confirmed both the difference in HDL and particularly HDL2 levels between the sexes which other authors had observed with reference methods, and the significant negative correlation between plasma triglycerides and HDL2 levels. This method may be applied easily, is rather cheap and, therefore, may be used more often in future.