Neuro17 - 22

Question 1

Why is regeneration in the nervous sytem important?

Answer 1

Damage very serious

Question 2

What are the two forms of PNS damage?

Answer 2

Crush or severance

Question 3

Does PNS damage lead to cell death?

Answer 3

Depends on proximity to cell body

Question 4

What is the result of denervating muscle?

Answer 4

Atrophy, AChR reversal to embryonic, MUSK increase

Question 5

What helps denervated muscle?

Answer 5

External electrical stimulation - prevents atrophy

Question 6

What does nervous regeneration require?

Answer 6

Schwann cells, supply of GFs, degree of sprouting from growth cone

Question 7

Which kind of nervous injury has better prognosis?

Answer 7

Crush

Question 8

Outline recovery of spinal cord injuries

Answer 8

Poor connection recovery - sprouting usually followed by failed regeneration, and degeneration (aspects of Wallerian degeneration). Cysts and glial scars tend to form

Question 9

What do CNS neurons avoid?

Answer 9

Oligos

Question 10

What improves CNS regeneration?

Answer 10

Removal of myelin and oligos, autoimmunisation to myelin

Question 11

Name a myelin protein that inhibits axon growth

Answer 11

Nogo-a

Question 12

Characterise Nogo-a

Answer 12

200kD - in oligos and developing neurons

Question 13

Characterise Nogo-b

Answer 13

55kD - in many cells

Question 14

Characterise Nogo-c

Answer 14

25kD - in muscle

Question 15

Outline some objections to the involvement of Nogo in nervous regeneration

Answer 15

No correlation between nogo and regenerative capacity, transplanted hippocampal neurons grow axons into myelin, musch myelin is removed by macrophages after damage, grey matter regen is poor too

Question 16

What are CSPGs?

Answer 16

Condroitin sulphate proteoglycans

Question 17

How are astrocytes supposedly involved in nervous regeneration?

Answer 17

Form glial scar - jumbled and fibrous - perhaps these impair regen

Question 18

How can we repair nervous damage?

Answer 18

Spinal cord bridges, foetal cell transplant, umbilican cell transplant, autologous transplants

Question 19

What are spinal cord bridges?

Answer 19

Plastic tubing filled with GFs, ECM synthetic matrix etc

Question 20

Where are adult nervous stem cells?

Answer 20

Hippocampus, olfactory epithelium, forebrain SVZ, dentate gyrus

Question 21

Explain the connection between anti-depressants and stem cells

Answer 21

Maybe promote new cell growth, hence why they take a few weeks to work