Lecture 26 - Nervous system and Neural Tissue Engineering

Question 1

Nervous System

Answer 1

• Peripheral nervous system

- Central nervous system

Question 2

Peripheral Nervous System

Answer 2

• Cranial nerves from brain
• Spinal nerves from spinal cord
• Sensory nerve bodies

Question 3

Central Nervous System

Answer 3

• Brain
• Spinal cord
• Optic, olfactory and auditory system

Question 4

Peripheral Nerve Injury

Answer 4

• Loss of function and disfigurement —> result of blunt trauma, penetrating objects, fractures or dislocations
• Need to be rejoined without tension

Question 5

Peripheral Nerve Healing

Answer 5

Requires that the parent cell survive:
- Injuries closer to spinal cord are more likely to cause nerve cell death
- Requires that degenerated myelin be cleared by macrophages
- Stimulate axonal regrowth
- Must realign original fascicles during surgery
Natural regeneration:
- 2-5 mm/day
- unlikely to regain all function

Question 6

Scaffold for Peripheral Nerve Regeneration

Answer 6

• Permeable —> O2 and fluid, cells (fibrin and fibroblast), macrophages
• Biocompatible —> nerve guide (no tension/contraction
• Collagen and silicon tubes most common
• Guiding growth of axons could make more effective (scaffold architecture, chemistry (gradient of cytokines))

Question 7

Central Nerve Injury

Answer 7

• Spinal cord
• Differ from PNS injuries because neuronal cell body death, not just axon injury
• Glial scar within injury which prevents axon regeneration