9 - Degneration of Neurones

Question 1

3 types of nerve damage?

Answer 1

• neuropraxia
  myelin
  function restored
• axonotomesis
  axon and myelin [CTissue intact]
  recovery occurs
• neurotmesis
  axon and CT severed
  no complete recovery

Question 2

neurones reaction minutes after injury?

Answer 2

• injury potentials
• no AP conductance
• leak intracellular fluid

Question 3

neurones reaction hours after injury?

Answer 3

astroglia surround degrade synaptic terminal

Question 4

neurones reaction days/weeks after injury?

Answer 4

prox seg - chromatolysis

• cell body swell
• overactive
• nucleus to periphery
• neuroma stump forms
• doesn’t die and can reinnervate

distal - Wallerian Degen

• lack nutrition
• axon digested [micoroglia]
• tissues preserved [guide axonal growth from prox]