[Atherosclerosis in familial hypercholesteremia possibly induced by defective HDL].

The distinct increase in the highly atherogenic plasma low-density lipoproteins (LDL) caused by the wellknown LDL-receptor defect is considered to be responsible for the development of atherosclerosis in familial hypercholesterolemia (FH). In contrast to the atherogenic LDL, the high-density lipoproteins (HDL) are considered to have a protective effect against the development of atherosclerosis and have hitherto been insufficiently investigated in association with FH. HDL2 are assumed to be important in the removal of free cholesterol from the peripheral tissue to the liver, but this hypothesis needs to be supported by further experimental investigations. In this study 18 patients (7 men/11 women) with familial hypercholesterolemia (FH) were compared with 18 healthy controls (8 men/10 women). From fasting plasma the following parameters were determined: cholesterol, triglycerides, phospholipids, HDL-cholesterol, by rate zonal ultracentrifugation the lipoproteins VLDL (very low-density lipoproteins), IDL (intermediate-density lipoproteins), LDL (low-density lipoproteins), HDL2 and HDL3, as well as the activities of lipoprotein lipase (LPL) and hepatic lipase (HTGL). In addition, the percentage composition of the major apolipoproteins (apo) of HDL2 and HDL3 were determined by polyacrylamide disc-gel electrophoresis. In LDL of patients with FH the percentage amount of protein was significantly (p less than 0.01) smaller than in controls. Furthermore, in HDL2 of patients with FH, the percentage content of apo-A II and apo-D was significantly (both p less than 0.01) higher than in controls. In HDL3 of patients with FH a significantly smaller (p less than 0.02) amount of apo-E was revealed than in controls.(ABSTRACT TRUNCATED AT 250 WORDS)