Over the past decade, the approach to the hyperlipidemic patient has developed from a vague trial and error affair to an increasingly precise and effective science. The major reason for this lies in our growing insight into the mechanisms involved in normal and abnormal lipid transport as well as the mode of action of hypolipidemic drugs.
Lipids, Lipoproteins, and Lipid Transport
All of the blood lipids (cholesterol, phospholipids, and triglycerides) are by definition insoluble in aqueous solution. Instead of being free in plasma, all lipids enter, circulate, and leave the blood bound to specific proteins. These lipid-protein complexes or lipoproteins have been defined operationally in the past according to the physical chemical systems used to isolate them. We speak in terms of the ultracentrifugal separation when we differentiate chylomicrons, very low density lipoprotein (VLDL), low density lipoprotein (LDL), and high density lipoprotein (HDL). They correlate reasonably well with electrophoretically defined
Levy RI. HyperlipoproteinemiaSome Basic Concepts on Diagnosis and Management. JAMA. 1973;226(6):648–649. doi:10.1001/jama.1973.03230060026008