Kolesterolupptag

Kolesterolupptag, also known as cholesterol absorption, refers to the process by which the body absorbs cholesterol from the gastrointestinal tract into the bloodstream. This process primarily occurs in the small intestine, where dietary cholesterol and biliary cholesterol are incorporated into micelles, facilitating their uptake by enterocytes (intestinal cells).

In the enterocytes, cholesterol is transported across the cell membrane by specific transporter proteins, such as Niemann-Pick C1-Like 1 (NPC1L1). Once inside the cells, cholesterol can be incorporated into chylomicrons and released into the lymphatic system, ultimately entering the bloodstream. This pathway plays a crucial role in maintaining cholesterol homeostasis and influences plasma cholesterol levels.

The efficiency of cholesterol absorption varies among individuals and can be affected by multiple factors, including genetics, diet, and the presence of certain medications. Some individuals have a genetic predisposition that results in higher or lower absorption rates, which can impact their risk of cardiovascular disease.

Medications like ezetimibe target the cholesterol absorption process by inhibiting NPC1L1, thereby reducing intestinal cholesterol uptake and lowering plasma LDL cholesterol levels. Understanding cholesterol absorption is important in managing conditions related to hypercholesterolemia and cardiovascular health.

Overall, cholesterol absorption is a vital physiological process that contributes to the regulation of cholesterol levels, alongside endogenous synthesis in the liver and other tissues.