The study will use 3H-cholesterol bound to albumin (particulate cholesterol) to assess the ability of HDL to transport cholesterol from the periphery to the liver to be eliminated. This process is called reverse cholesterol transport (RCT) and is one of the main mechanisms by which HDL protect against atherosclerotic cardiovascular disease. Mutations in some of the genes affecting HDL metabolism, may results in changes in RCT. The validation of a method assessing RCT is important for the development of new drugs which affect RCT and may result in useful treatments for atherosclerosis.~Subjects carrying mutations in genes known to affect HDL metabolism and healthy controls will be enrolled in the study. Changes in the tracer activity in total plasma, lipoproteins fractions and feces will be analyzed following the intravenous administration of radiolabeled particulate cholesterol.
The purpose of this study is to investigate the use of radiolabeled particulate cholesterol administered intravenously in association with albumin, as a method to study reverse cholesterol transport (RCT) in people carrying mutations in genes known to affect high density lipoprotein (HDL) metabolism by analyzing changes in the tracer activity in total plasma, lipoproteins fractions and feces.