[The apolipoproteins in man ].

Twelve different apolipoproteins have been described in human serum. Apo A-I and apo A-II are essential for the structure of the HDL particles and for the function of LCAT activity. Apo B is the main protein in LDL but does also occur in the triglyceride-rich particles. Apo B represents the binding protein for the LDL-receptor pathway. The C-apolipoproteins are located on the surface of VLDL. They are transferred to HDL throughout the catabolism of VLDL and affect lipoprotein lipase activity. This enzyme is also affected by the E-apolipoproteins which occur in the triglyceride-rich particles as well as in HDL. Apo E is the binding site for another specific cell receptor. The concentration and metabolism of apolipoproteins is affected by diet, drugs, hormones, body weight, alcohol, cigarettes, physical exercises, liver and renal diseases. There is a close relation between apolipoproteins and atherosclerosis.