Coronary Heart Disease

Question 1

Where is LDL deposited

Answer 1

Subintimal space - bind to proteoglycan

Question 2

Progression of atherosclerosis

Answer 2

Adaptive thickening of smooth muscle
Macrophage foam cell formation - Type II lesion
Small pools of extracellular lipid - Type III (preatheroma)
Core of extracellular lipid - Type IV (atheroma)
Fibrous thickening - Type V
Thrombus and fissue and hematoma - Type VI (complicated)

Question 3

Natural history of atherosclerosis

Answer 3

Normal
Intermediate lesions
Advanced lesions
Complications (stenosis, plaque rupture)

Question 4

Cell involved in atherosclerosis

Answer 4

Endothelial
Platelets
Monocyte macrophages
Vascular smooth muscle cells
T lymphocytes

Question 5

Classes of macrophages

Answer 5

Inflammatory - kill microorganisms
Resident - homeostatic - suppress inflammatory activity, alveolar resident macrophages - surfactant lipid homeostasis, osteoclast - calcium and phosphate homeostasis, spleen - iron homeostasis

Question 6

LDL

Answer 6

Carry cholesterol from liver to rest of body including arteries

Question 7

HDL

Answer 7

Carry cholesterol from peripheral back to lungs

Question 8

Familial hyperlipidemia

Answer 8

Autosomal genetic disease
Elevated cholesterol
Fail to clear LDL from blood
Xanthoma and early atherosclerosis

Question 9

Macrophage scavenger receptor A

Answer 9

CD204
Bind to oxidised LDL
Bind to gram positive bacteria

Question 10

Macrophage scavenger receptor B

Answer 10

CD36
Bind to oxidised LDL
Bind to malaria parasite and dead cells

Question 11

Oxidative enzymes of macrophages

Answer 11

Modify native LDL
NADPH oxidase
Myeloperoxidase

Question 12

Macrophage cytokine mediators that recruit monocytes

Answer 12

Cytokines - IL-1 upregulate cell adhesion molecule VCAM-1

Chemokines - MCP-1 bind to receptor CCR-2

Both reduce atherosclerosis

Question 13

Macrophage growth factors

Answer 13

Platelet derived growth factors - vasc smooth musc cell chemotaxis, survival, mitosis

Transforming growth factor beta - increasef collagen synthesis and matrix

Atherosclerotic - decreased contractile filaments and increased matrix

Question 14

Macrophage proteinase

Answer 14

Metalloproteinase

Degrade tissue

Question 15

Macrophage apoptosis

Answer 15

Protective system in face of toxic lipid overload
Once overwhelmed, die via apoptosis
Release toxic lipids into lipid necrotic core
Toxic material accumulate, until plaque ruptures causing it to meet blood