Endoteellrakud

Endoteellrakud, often referred to as endothelial cells, form the inner lining of all blood and lymphatic vessels. They are a specialized type of epithelial cell, but their location and function distinguish them. These cells play a critical role in maintaining vascular homeostasis, acting as a barrier between the blood and surrounding tissues.

The primary functions of endoteellrakud include regulating the passage of substances into and out of the bloodstream through their selective permeability. They also produce various molecules that influence blood clotting, inflammation, and the tone of blood vessels. For example, they can release nitric oxide, a potent vasodilator, which helps to relax blood vessels and improve blood flow. Conversely, they can also release substances that promote clotting and inflammation when the body is injured.

Endoteellrakud are not merely a passive lining. They are metabolically active and constantly interact with their environment. They participate in the immune response by expressing adhesion molecules that allow white blood cells to attach and migrate into tissues. Furthermore, they are involved in angiogenesis, the formation of new blood vessels, which is essential for growth and repair.

Dysfunction of endoteellrakud is implicated in a wide range of diseases, including atherosclerosis, diabetes, and hypertension. Damage to these cells can lead to impaired blood flow, increased inflammation, and a higher risk of blood clots. Maintaining the health of endoteellrakud is therefore crucial for overall cardiovascular health.