Cardiovascular

Question 1

What is the endothelium

Answer 1

A mini layer of endothelial cells lining the blood interface throughout the CVS including cardiac chambers

Critical to vascular health

Question 2

What is the glycocalyx?

Answer 2

A carbohydrate rich protective layer covering the Endothelium

Regulates permeability
Controls Nitric Oxide production
Acts as a mechanosensor of blood shear stress

Easily damaged by:
inflammation
Hyperglycaemia
Endotoxemia
Oxidised low density lipoproteins

Question 3

What does damage to the glycolax result in?

Answer 3

Further damage to the endothelium

Promoting lipid deposition and atherosclerosis

Question 4

List Key functions of the endothelium

Answer 4

Semi permeable barrier - fluid balance, host defence and movement of substances (oxygen & glucose)
Regulates vascular tone - vasodilation (NO) & vasoconstrictors (endothelin)
Enzymes - ACE (angiotensin converting enzyme)
Angiogenesis - Endothelium cells are where all new blood vessels are generated from.
Haematostasis - prevents platelet adherence and coagulation.
Immune defence - deflects while blood cells

Question 5

What are Vascular smooth muscle cells?

Answer 5

Found in the tunica media (middle)
Key in blood vessel contraction and dilation

Controls the integrity and elasticity of blood vessels and limits immune cell infiltration along with the endothelium.

Question 6

What is the role of Nitric Oxide (NO) in Cardiovascular health?

Answer 6

Regulates vascular tone
Reduces platelet aggregation and vascular smooth muscle cell proliferation
Inhibits leukocyte adhesion & inflammatory cytokines
Opposes oxidation of LDL’s
Generated from L-ARGININE by endothelium enzyme eNOS
Vitamin D regulates NO synthesis through eNOS
Reduced NO contributes to atheroma formation and CVD

Question 7

What is the normal function of the Endothelium and the Vascular smooth muscle cells?

Answer 7

Endothelial cells:
Impermeable to large molecules,
anti inflammatory
Deflects leukocylte adhesion
Enhances vasodilation
Resists thrombosis

Vascular smooth muscle cells:
Normal contractile function
Maintains extra cellular matrix
Contained within the tunica media

Question 8

What is the function of the Endothelium and vascular smooth muscle cells after oxidative stress and inflammation

Answer 8

Endothelial cells
Increased permeability
Increased inflammatory cytokines
Increased leukocyte adhesion
Reduced vasodilator molecules (NO)
Increased risk of thrombosis

Vascular smooth muscle cells
Increased inflammatory cytokines
Increased extra cellular matrix synthesis
Migration into the tunica intima and proliferation of vascular smooth muscle cells.