RESUMEN
Case control and prospective epidemiology studies have found a striking, consistently negative association between High Density Lipoprotein [HDL] levels and coronary vascular events. As a result, the genetic and environmental determinants of HDL levels are being studied intensively. These investigationS and their potential clinical applications require a fundamental understanding of the structure, function and metabolism of HDL and its components. Of the special interest are the means by which it exerts its apparently protective effect. In this report we characterize the structure of HDL and describe its components, particularly the protein component. We discuss HDL metabolism in light of the relationship of HDL to other lipoprotein classes and relate what little is known of the functions of HDL. We also review the biochemical mechanism by which HDL may protect against cardiovascular disease and discuss further biochemical research that will be necessary for a better understanding of HDL. Interest in HDL has been greatly intensified in recent years, stimulated largely by the finding that HDL is inversely related to coronary artery disease. Case-control and prospective observations of the striking, consistent and independent negative association between HDL levels and coronary vascular have in turn generated new interest in the structure, competitive and metabolism of these fascinating lipoproteins. Several studies carried out in Pakistan also reveal the inverse relation of HDL to HDL1,2. This article contains a tremendous amount of information on HDL and its relationship to genetic and environmental factors which should be useful to investigators and clinicians in their evaluation and use of HDL cholesterol measurements to assess heart disease risk. A knowledge of the structure, function and metabolism of HDL and its components is essential to understand what is being measured, and by what molecular mechanisms HDL may prevent or retard vascular disease