Neurological Medicine - Drewes

Question 1

Brain uses what % of oxygen and glucose in your body

Answer 1

Brain uses 25% of your glucose

Brain uses 20% of your oxygen

Question 2

Apart from glycogen synthesis and the TCA cycle, what is another metabolic fate for glucose? How is it important for the body?

Answer 2

The pentose phosphate pathway
Makes NADPH
used for anabolic synthesis (like synthesis of fatty acids)
Also makes ribose-5-phosphate for synthesis of nucleotides

Question 3

Good review question:

What are the two important regulatory steps of glycolysis?

Answer 3

Phosphofructokinase

Pyruvate Kinase

Question 4

What is the formula for CMR-G

Answer 4

CMR-G = (A-V)F/W
A=arterial conc.(mole/l)
V=venous conc.(mole/l)
F=blood flow (l/min)
W=weight (g)
CMR Units=moles/g/min

Question 5

IF someone has a seizure, what’s going to happen to their CMRG and CMRO2?

Answer 5

They will both increase because the neurons are firing and using up a lot of both, so the body needs to replenish them.

Question 6

What would happen to a person’s CMRG and CMRO2 if they had a stroke?

Answer 6

CMRG increases to maitnain ATP

CMRO2 is maxed out so can’t increase

Question 7

Why in the brain when a particular area is stimulated, do you see an increase in blood flow, glucose use, and oxygen availability BUT no increase in oxygen use in these areas?

Answer 7

Because glucose is broken down anaerobically through lactate rather than going through the TCA cycle!

Question 8

Babies utilize what for metabolism?

Answer 8

babies - mostly keotgenic diet because of the fats contained in milk

Question 9

What is the advantage of using ketones in the TCA cycle?

Answer 9

Use 28% less O2 for the same amount of ATP

Question 10

If someone is drowning, what is their CMRG and CMRO2 going to be like?

Answer 10

GLucolysis will be increased to to maintain ATP

O2 will go down because it is not around underwater

Question 11

What did Lou Solokoff prove with his rhesus monkey vision deprivation experiment?

Answer 11

He compared monkeys with no deprivation, bilateral deprivation, and single eye deprivation

In comparing brains he saw in the total deprived and undeprived, ther brain was either all stimulated or dormant.

In the halfsies, he saw that it was actually an alternate banding pattern throughout the section. Meaning they had ocular dominance columns

Question 12

What is the importance of astrocytes in a neuron’s use of glucose?

Answer 12

Astrocytes actually take up glucose and then convert it to lactate so that they can shuttle it over to neurons.