Postsynaptic Neuronal Activity Promotes Retinal Axon Regeneration

The distal injury is different from the optic nerve crush as the lesion site is caudal to the chiasm, not as severe, and RGC axons retain collaterals in some visual targets anterior to the lesion. These conditions cause degeneration in some RGCs therefore mimicking injuries that occur in clinical settings, as well as other degenerative optic neuropathies.

We haven’t yet looked at how different RGC subtypes are uniquely affected.

In the CNS, degenerating processes should be cleared between 30-90 days.

The injury is a partial injury that severs some axons while other axons remain connected, i.e. spared.

We haven’t tested this yet.

No.

It does indicate that activity promotes regeneration, but the current data does not test the role of activity in regeneration vs reconnection.

Yes retrograde labeling shows that there is a threefold increase in the number of RGCs labeled in the retina in the activity group compared to controls, indicating that injured axons are regenerating. However in addition to injured axons regenerating, spared axons are likely to be sprouting collaterals.

We haven’t looked at the role of immune cells in our model yet.

Glaucoma and other degenerative diseases where some RGC axons degenerate over time are likely to show similar pathologies.