[Characteristics of cholesterol transport by various classes of lipoproteins and their apolipoproteins in hypo- and hyperalphalipoproteinemia].

The content in the blood plasma of the main apolipoproteins of lipoproteins of very low and low density apo-B and tetramethylurea-soluble apo-LP as well as lipoproteins of high density apo-A and the relation to apo-LP cholesterol of these classes of lipoproteins were studied in 34 males with different levels of alpha-LP cholesterol. It is shown that in hypoalphacholesterolemia the plasma apo-A content is reduced with the cholesterol/apo-A ratio being less than in normoalphacholesterolemia; at the same time, the content in the plasma of total triglycerides, cholesterol, and protein of very low density lipoproteins is increased and cholesterol saturation calculated for protein of very low and low density lipoproteins does not change. In hyperalphacholesterolemia the plasma apo-A content is increased both in the absolute amount and in relation to apo-B and TMU-soluble proteins; the content of cholesterol on apo-A in high density lipoproteins is the same as under normal conditions and higher than in hypoalphacholesterolemia. The results obtained are discussed in association with the data in the literature concerning the functions of lipoproteins and apo-LP in relation to the transport of cholesterol into the vascular wall and its drainage.