The function of endothelial cells

Question 1

In what ways do endothelial cells act as a permeability barrier?

Answer 1

endothelial cells have a certain permeability due to transcytosis and the fact that some of them have fenestrations

Question 2

How are endothelial cells important in terms of the basal lamina?

Answer 2

endothelial cells synthesise components of the basal lamina

Question 3

How are endothelial cells involved in haemostasis?

Answer 3

1. endothelial cells synthesise and secrete molecules that promote blood clotting on injury e.g. Factor Viii
2. they also synthesise and secrete molecules that prevent inappropriate blood clotting e.g. NO, prostacyclin and thromobodulin

Question 4

How are endothelial cells involved in vasodilation?

Answer 4

Endothelial cells secrete vasoactive factors - promote NO/prostacyclin
- or inhibit vasodilation - endothelin 1

Question 5

How are endothelial cells involved in the immune response?

Answer 5

endothelial cells PRODUCE INFLAMMATORY MEDIATORS

• secrete interleukins in response to damage or detection of any kind of pathogenic
• secrete cytokines - to promote/attract wbc to that particular blood vessel or network of capillaries

Question 6

How can endothelial cells regulate the division of cells around them (in response to changes in the human condition)?

Answer 6

endothelial cells produce so GF e.g. fibroblast growth factor and platelet derived growth factor
GF are proteins that control the division of cells

Question 7

summarise the roles of endothelial cells

Answer 7

1. permeability barrier
2. synthesise components of the basal lamina
3. synthesise and secrete molecules that promote blood clotting on injury
4. synthesise and secrete molecules that prevent inappropriate blood clotting
5. secrete vasoactive factors that promote or inhibit vasodilation
6. produce inflammatory mediators e.g. interleukins
7. produce some growth factors - FGF, PDGF