Block 1 Brain Barriers

Question 0

How far is the farthest a neuron is from a capillary?

Answer 0

18 microns

Question 1

What area does the blood brain barrier (BBB) breakdown in aging humans?

Answer 1

The hippocampus

Associated with mild cognitive impairment

Question 2

What cells surround capillaries making the BBB?

Answer 2

Pericytes and maybe astrocytes

Question 3

What are the three components of tight junctions in the BBB?

Answer 3

Claudin
JAM (junctional adhesion molecule)
Occludin

Question 4

What are the two sides of the capillary endothelial cells?

Answer 4

Luminal - in the lumen

Abluminal - toward the capillary wall

Substances must pass through two layers and the cytoplasm which is an enzymatic barrier

Question 5

How can things pass through the BBB?

Answer 5

Lipid soluble can diffuse

Transporter proteins

Question 6

What transports lactic acid (among other things) across the membrane and is dr. Drewes’s favorite membrane protein?

Answer 6

MCT1 - mono carboxylate transporter 1

Also let’s ketones and pyruvate through

Very many of these

Question 7

What may be better treatment for treating low blood sugar in neonates?

Answer 7

Ketone bodies

Question 8

What is P- glycoprotein?

Answer 8

One of several drug efflux transporters

It is a 12TM ABC transporter

Question 9

What two genes are key in p glycoprotein?

Answer 9

Mdr1a and Bcrp1

Question 10

What are the pathways between the blood and brain?

Answer 10

Transcytosis where there is a shuttle protein

Immune cell migration where they somehow pass tight junctions

Transcytosis is way more likely to happen

Question 11

How can you better deliver drugs through the BBB?

Answer 11

By making them compatible with transcytosis proteins.
Like angiochem (pacitaxol) which nap binds to LRP-1

Question 12

What is diapedesis?

Answer 12

Where cells move through tight junctions like immune cells through the BBB

Question 13

What are the two stages of diapedesis?

Answer 13

Rolling - weak adhesion
Emigration - strong adhesion

Started by inflammatory responses

Question 14

When is the BBB developed?

Answer 14

When the very first vessels form

Question 15

What signals are needed for new blood vessel development in the brain?

Answer 15

Wnt7a/7b and a pericyte

Question 16

What cells are needed for CSF development?

Answer 16

Ependymal cells

Question 17

What transporters are needed for CSF secretion?

Answer 17

Na, K, and HCO3
H and Cl
Aquaporin
The Na, K, and Cl transporter is the most important which puts Cl, Na, and K out.

Question 18

What drugs reduce CSF production?

Answer 18

Lasics?
Furosemide
Ouabain
Acetazolamide

Question 19

What is the method of glymphatic system?

Answer 19

Supports interstitial fluid and solute clearance from the brain

The fluxes of CSF and ISF propel the waste into the veins then directly into the lymphatic system where it is cleaned by the liver and kidney