Blood-Brain Barrier

Question 1

What is the blood brain barrier composed of?

Answer 1

A series of morphological components coupled with physiologcal properties

Question 2

What joins the endothelial cells of the blood capillaries in the CNS?

Answer 2

Tight junctions

Question 3

Tight junctions form a barrier that allow for what?

Answer 3

Selective exchange of only small molecules

—therefore Large proteins such as antibiotics are restricted from crossing this barrier

Question 4

How are substances such as glucose and amino acids transported across the Blood-brain Barrier? And for what reason?

Answer 4

Active transport for nourishment of the CNS

Question 5

What is the roll of Glial Cells?

Answer 5

To control the permeability of the endothelial cells by influencing the physiology of endothelial cell membranes

***essentially they maintain homeostasis

Question 6

If Gilial Cells become disrupted what is the result?

Answer 6

They no longer control endothelial cells and the barrier is made more permeable

Question 7

Why is it important that the barrier be patent at all times?

Answer 7

Because Neurons do not have storage capability

Question 8

True or False:

Areas of high activity show the highest uptake of necessary substances

Answer 8

TRUE

Question 9

One might see an increase in perfusion rate of the capillary beds in what areas?

Answer 9

Areas of greater physiological activity

Question 10

Experimental evidence following uptake of radioactive labeled compounds (ie. glucose) provides helpful information why?

Answer 10

Allows for ongoing view of the CNS with areas of higher glucose or O² indicating areas of the CNS most involved as various tasks are occuring