lipoprotein /lip′ōprō″tēn/ [Gk, lipos + proteios, first rank] , a conjugated protein in which lipids form an integral part of the molecule. They are synthesized primarily in the liver; contain varying amounts of triglycerides, cholesterol, phospholipids, fat-soluble vitamins, and protein; and are classified according to their composition and density. Practically all of the plasma lipids are present as lipoprotein complexes. The elevation of low-density lipoproteins (LDLs) in plasma is associated with an increased risk of atherosclerosis. Normal adult levels of lipoproteins include high-density lipoproteins, greater than 35 mg/dL; LDLs, 60 to 180 mg/dL; and very low-density lipoproteins, 25% to 50%. Kinds include chylomicron, high-density lipoprotein, low-density lipoprotein, very low–density lipoprotein.
