Enigma- From NB Flashcards
Enigma of CNS repair (14 cards)
Why do adult CNS axons fail to regenerate after injury?
Axon gets lost to target as it sprouts- loss of aligned glail pathways and axonal guidance.
Glail scarring- creates a barrier of inhibition
Why are olfactory ensheating cells a promising theraputic approach?
Olfactory system continually forms neruons throughout life
Define plasticity (1969)
Neurons in the grey matter has the ability to form new connections after injury in adult.
now consider WM damage is a crucial part too
How do synapse connection reform following nerve injury?
adjacent synapsed take over denervated sites
What is the contents of white matter fibre tracts?
myleinated axons
glail cells e.g. oligodendrocytes, CSPGs,astroytes, microglia
State the inhibtory molecues to axonal regneration
NOGO-A and CSPGs
Define NOGO-A
Potent myelin-associated inhibitor for axonal growth from oligodendrocytes
Adult neurogenesis of OECs
Continually replaced by stem cells
Only area of NS where neruonal regenration occurs throughout life
Olfactory system
why? - To smell new things
Advantages of using OECs axons comapred to schwaan cells?
Their axonla processes migrate and extend from PNS to the brain (CNS) whereas schwaan cells only stay in transplanted area.
OEC cell type and function?
Glial cell involved in regeneration of olfactory nerve fibers
Shown promise in cell transplantation therapies for CNS injuries.
How do astrocytes facilitate axonal migration from PNS to CNS
OEC and astrocyte crosstalk
OECs block pro-inflammatory nuclear NFκB translocation in astrocytes
Which model subtantiated OECs abilty to aid axonal regeneration into CNS
Spinal root lesions- brachial plexus injury model.
Normally with this injury type the green peripheral nerves would not be able to innervate the CNS upon regeneration axon branching because of the astrocytes not allowing them in.
They cultured the OECs cells from the olfactory bulb and injected them in the boundary between peripheral nerves and CNS astrocytes.
What are Pattern Electroretinograms recordings
a type of electrophysiological test that assesses the electrical activity of the retina in response to a pattern-reversing stimulus
