Transport of Cholesterol

Cholesterol consists of nonpolar rings, so is completely insoluble in water. Therefore it has to be transported in lipoproteins as either bile salts or cholesteryl esters.

There are different densities of lipoproteins,

LDL is sometimes known as "bad" cholesterol and is responsible for transporting cholesterol form the liver. HDL is known as "good" cholesterol and is responsible for transporting cholesterol to the liver. Heart disease is associated with high LDL levels and low HDL levels.

Peripheral tissues obtain most of their cholesterol from LDL, and cholesterol continuously circulates back and forth between the liver and peripheral tissues.

Dietary cholesterol and cholesteryl esters are transported in the blood by intestinally synthesised lipoproteins called chylomicrons and are taken to the liver where it is either: