Lipids and lipoproteins

Abstract

Abstract Cholesterol is a sterol which is essential for the synthesis of cell membranes and various hormones. It is transported in the plasma in macromolecular solubilizing complexes termed lipoproteins. The cholesterol concentration is an aggregate measure of the total amount of cholesterol carried in the various lipoproteins. About two-thirds of cholesterol in plasma is transported as low density lipoprotein (LDL) cholesterol. In excess it is potentially atherogenic which explains the relationship between elevated total cholesterol concentrations and coronary heart disease (CHD). High density lipoprotein (HDL) cholesterol accounts for 15-25 per cent of the total plasma cholesterol. It plays a major role in the mobilization and removal of tissue cholesterol and its concentration has been shown to be inversely related to the incidence of CHD. Very low density lipoprotein (VLDL) accounts for only about 10 per cent of total cholesterol but for over half of triglyceride concentration in the normal subject with the remaining triglycerides transported by other lipoproteins.