Topic 19: Nervous System - CNS Protective Features - BBB and Cerebral Arterial Circle Flashcards
1
Q
What are the 2 cell types of the blood brain barrier?
A
- endothelial cells of capillaries with tight junctions
- astrocytes
2
Q
What do astrocytes do?
A
- foot processes wrap around endothelial cells
3
Q
What type of permeability is the blood brain barrier?
A
selectively permeable
4
Q
What does selective permeability of the BBB allow for? (2)
A
- allows glucose and fat soluble material in
- does not allow toxins, antibiotics, etc.
5
Q
What is the cerebral arterial circle?
A
- cerebral arteries form circle at base of forebrain
6
Q
What does the cerebral arterial circle circle?
A
- pituitary gland and optic chiasma (where optic nerves cross)
7
Q
What does the cerebral arterial circle unite?
A
- unites the two major blood supplies to the brain (anterior and posterior)
8
Q
What does the cerebral arterial circle provide, if vessels are blocked?
A
- alternate route for blood
9
Q
Blood flow to brain posteriorly
A
vertebral arteries -> basilar artery -> posterior cerebral arteries
10
Q
Arteries of the brain diagram
A
11
Q
Blood flow to brain anteriorly
A
12
Q
Blood return from brain diagram
A
