Vascular Endothelium Flashcards
Where do most endothelial cells reside?
In the microvasculature
Name the 3 layers of blood vessels from innermost to outermost
Tunica intima
Tunica media
Tunica adventitia
What is the tunica intima made of?
Endothelium
What is the tunica media made of?
Smooth muscle cells
What does the tunica adventitia contain?
Vasa vasorum
Do all blood vessels have 3 layers?
No capillaries and venules don’t, they have one layer of endothelium
What supportive cells are present in the basement membrane of capillaries and venules?
Mural cells aka pericytes
What are the factors produced by blood vessels that are needed to maintain tissue homeostasis called?
Angiocrine factors
What are angiocrine factors?
Factors produced by blood vessels that are needed to maintain tissue homeostasis
How thick are endothelial cells?
1-2 micrometres
What is the diameter of an normal endothelial cell?
10-20 micrometers
What is contact inhibition?
When 2 endothelial cells come together and stop growing
How often do endothelial cells proliferate?
Very rarely, they have a long lifespan and will only proliferate when new blood vessels are required
What are some functions controlled by the endothelium of blood vessels?
Tissue homeostasis and regeneration Permeability Vascular tone Inflammation Angiogenesis Haemostasis and thrombosis
What type of cell are endothelial cells?
Heterogeneous
Why is dysfunction of the endothelium so significant?
It contributes to disease more than any other organ, this includes ischaemia, cancer, diabetes etc
What is tissue specific microvasculature?
The idea that not all blood vessels are the same and have adaptations depending on which tissue they supply
What are the characteristics of resting endothelium?
Anti inflammatory
Anti thrombotic
Anti proliferative