What collects in an atherosclerotic plaque?
Inflammatory/immune cells, smooth muscle cells, lipids, connective tissue
What are the three stages of atherosclerotic plaque formation?
What is a genetic predisposition that can accelerate atherosclerotic plaque formation in the first decade of life?
Homozygous Familial Hypercholesterolemia
Where do atherosclerotic lesions generally form?
Where shear stress is low but fluctuates rapidly
What gene expression increases at sites prone to plaque development? What cells do these genes help recruit?
Monocytes/Macrophages
What factors does lipid accumulation depend on?
Disruption of the integrity of the endothelial barrier through cell loss and/or cell dysfunction
Describe the relationship betwixt LDL and atherosclerosis.
What is the likely effect of oxidized lipoproteins in the evolution of atherogenesis?
Ox. lipos. induce tissue damage and recruit macros which can transform the normal anticoagulant vascular surface to a procoagulant one
When a thrombus forms on the early atherosclerotic plaque, what 3 things can occur?
Thrombus may
What occurs when the plaque separates the intima from the nutrient-rich blood?
Intima undergoes ischemic necrosis. Macros as well as platelets release angiogenic factors causing new vaso vasorum to form
What cytokine is a key regulator of ECM deposition in atherosclerotic plaques?
TGF-Beta
Describe the adaptation stage of atherosclerosis
How can hemorrhage occur in the atherosclerotic plaque?
Fragile new vessels are formed within the plaque and can rupture
What are the two precursor lesions of atherosclerosis?
What is the characteristic plaque of atherosclerosis? Characteristics?
The fibroinflammatory lipid plaque; Well defined borders, irregular shape
What is a more advanced lesion than a fibroinflammatory lipid plaque?
Fibrofatty plaques
What separates the lumen of the blood vessel from the necrotic center of the atherosclerotic plaque?
The fibrous capsule
What is an important contributor to plaque growth and subsequent complications?
Neovascularization
What are the possible states of a complicated atherosclerotic plaque?
What causes the formation of a mural thrombus?
Abnormal blood flow around the plaque
What major cytokine within the necrotic center of the plaque is thrombogenic?
Tissue Factor
What are complications of atherosclerosis?
What is restenosis? What causes it?
Following percutaneous transluminal coronary angioplasty, stenosis again occurs; Intimal hyperplasia due to SM proliferation
What are risk factors for atherosclerosis?