Smooth Muscle Cell
Many parts of the vasculature are lined with smooth muscle cells. These cells have the ability to contract and relax in order to regulate the diameter of the vessel they wrap around. This in turn regulates blood flow and blood pressure.
Capillaries are the smallest vessels in the body. They are so small that only a single red blood cell can pass at a time. They are also very thin (lacking any smooth muscle), which allows for gas exchange with tissues.
Arteries are the largest blood vessels in the body. They carry large amounts of blood, and have a large outer muscular layer composed of many smooth muscle cells.
Marfan Syndrome is a genetic disorder of connective tissue. A mutation in the FBN1 gene causes a disruption in the production of connective tissue throughout the body. This leads to a wide variety of symptoms with some of the classic ones being tall stature, long limbs, eye problems, and aortic aneurysms.
Hemangiomas are abnormal growths of capillaries. These are benign (not cancer) and are called "strawberry marks" as they often appear as a red, raised patch on the skin. In infants, these usually resolve on their own.
Atherosclerosis is a disease where fatty plaques build up inside blood vessels. There are many risk factors for developing these plaques, such as an unhealthy diet, obesity, and high cholesterol levels. If a plaque ruptures, a clot can form which can be dangerous as it cuts off the blood supply of that vessel.
Marfan -> Smooth Muscle Cell
The main danger of Marfan Syndrome is the production and rupture of an aortic aneurysm. To help decrease pressure in these aneurysms, the beta 1 blocker metoprolol can be used, which decreases heart rate and thus pressure inside the vasculature.
Hemangioma -> Capillary
Due to a not fully understood mechanism, the nonselective beta blocker, propranolol, can be used to shrink infant hemangiomas.
Atherosclerosis -> Artery
Since it is extremely difficult to remove plaques that have already built up in patients with atherosclerosis, the main treatment approach is to prevent further plaque buildup. This can be performed with a statin, such as rosuvastatin, which inhibits the production of cholesterol by the liver.