Arteriosclerosis, Thrombosis and Vascular Biology

Arteriosclerosis: Arteriosclerosis refers to condition where blood vessels that carry oxygen and nutrients from heart to the rest of body become thick and stiff restricting the blood flow to organs and tissues. This damage permits a collection of substances, known as plaque that builds up in the artery wall. These substances involve fat and cholesterol.

There are 5 stages of atherosclerosis;

• Endothelial dysfunction
• Lipid layer formation
• Leukocytes and smooth muscle cells migration into the vessel wall
• Foam cell formation 
• Degradation of extracellular matrix

Thrombosis: Thrombosis involves the formation of a blood clot formed in a blood vessel known as a thrombus. This clot block or obstruct blood flow in the affected area, and cause serious complications if this clot moves to an essential part of the circulatory system, such as the brain or the lungs.

There are 2 main types of thrombosis:

• Venous thrombosis refers to the blood clot that blocks a vein.
• Arterial thrombosis refers to the blood clot that blocks an artery.

Vascular Biology: Vascular biology is the study of the biology of the constituent cells of the vascular wall. It includes the heart and blood vessels. The blood vessels comprise arteries that transport blood from your heart to the rest of body, and veins that return the blood from all parts of the body to your heart. Blood vessels are made up of three layers.

• The inner layer called as intima is lined by specialized cells called endothelial cells. It prevents the vessels from clotting.
• The middle layer called media is composed of muscle cells, and allows the vessels to expand and contract.
• The outer layer called adventitia offers strength so that the blood vessels do not burst under pressure.