Atherosclerosis Flashcards
First 5 steps
Damage to endothelial
Platelets adhere to damaged wall
Infiltration of ldl into intima causes inflammation
Ldl oxidised causes endothelium to release leukocytes adhesion molecules
Oxidised ldl taken up by scavenging macrophages turning into foam cells
Second 5 steps
Oxidised ldl has a deformed lipoprotein b component
Surface proteins vascular cell adhesion molecule (vcam) to
Make endothelium sticky
Platelets attract to the vcam area
Monocytes and lymphocytes adhere
To vcam
Monocytes differentiate into macrophages
Final 6
Foam cells release chemical messengers which cause mRNA to produce further inflammation
T-cells release growth factors that cause proliferation and attraction of smooth muscle to area
Fatty plaque develops
Plaque has rough surface for platelet ahdesion
Hard fibrous cap developed
What causes immune response
Microbes
What do microbes do
Cause immune response by macrophages and T cells
Immune response releases what
Cytokines
Proteases
Prothrombotic and procoagulant agents
What’s does cytokines do
Reduce stability of plaque making it more likely to rupture
What do proteases do
Weaken collagen of plaque
What do pro thro and pro coag do
Cause a clot when the plaque ruptures
What can damage endothelium
Wear and tear Fibrinogen Free radicals Increased bp Turbulent flow Viral attacks Carbon monoxide
Other issues of damage to endothelium
Interfere with normal anti clotting function
Nitric oxide
Stenosis
Arterial enlargement can keep lumen open even with large plaque
Characteristics of endothelium
Permeable barrier
Produces growth factors in response to damage
Releases platelet aggregation clotting and anti clotting substances
Normally blood cells do not adhere
