HDL
Alternate Names : High-Density Lipoprotein
Definition This is a test that measures the amount of high-density lipoprotein (HDL) cholesterol in serum.
Pictures & Images
See all Pictures & Images
Why is the Test Performed?
This test is used in an evaluation of coronary risk factors.
Lipoproteins are proteins in the blood that transport cholesterol, triglycerides, and other lipids to various tissues. The main function of HDL appears to be carrying excess cholesterol (and probably other phospholipids and proteins) to the liver for "re-packaging" or excretion in the bile.
Higher levels of HDL seem to be protective against coronary artery disease, thus HDL is sometimes referred to as "good" cholesterol. The laboratory test for HDL actually measures the cholesterol part of HDL, not the actual concentration of HDL in the blood.
This is also true of the tests for low density lipoprotein (LDL) and very low density lipoprotein (VLDL). The total cholesterol level is the sum of LDL, HDL, and VLDL cholesterol.
|