Regenerating axons from adult chick retinal ganglion cells recognize topographic cues from embryonic central targets

AbstractWe investigated whether regenerating mature axons recapitulate embryonic features essential to successful reconnectivity within the injured nervous system. Strips from embryonic and adult chick retinae were cultured, and outgrowing axons were examined morphometrically and immunohistochemically. In addition, the target-recognition properties of adult neurites were analyzed. Regenerating adult axons elongate on a poly-L-lysine/laminin substratum with a speed about one order of magnitude slower than that of embryonic axons. Morphologically, adult axonal tips differ dramatically from embryonic growth cones in that they possess only filopodial extensions whereas embryonic growth cones possess both lamellipodial and filopodial processes. Both embryonic and adult neurites express the growth-associated protein GAP-43. When cultured on alternating stripes of anterior and posterior embryonic tectal membranes, both adult and embryonic retinal axons distinguish between the two membrane preparations. Our results demonstrate that during axonal regeneration the mature neurons express embryonic properties that are involved in the recognition of tectal positional cues.

Download Full-text

Axonal regeneration and synapse formation in the superior colliculus by retinal ganglion cells in the adult rat

Journal of Neuroscience ◽

10.1523/jneurosci.07-09-02894.1987 ◽

1987 ◽

Vol 7 (9) ◽

pp. 2894-2909 ◽

Cited By ~ 393

Author(s):

M Vidal-Sanz ◽

GM Bray ◽

MP Villegas-Perez ◽

S Thanos ◽

AJ Aguayo

Keyword(s):

Superior Colliculus ◽

Retinal Ganglion Cells ◽

Axonal Regeneration ◽

Synapse Formation ◽

Ganglion Cells ◽

Retinal Ganglion ◽

Adult Rat

Download Full-text

Glucocorticoid effects on axonal regeneration of retinal ganglion cells in vitro

Restorative Neurology and Neuroscience ◽

10.3233/rnn-1994-6201 ◽

1994 ◽

Vol 6 (2) ◽

pp. 83-87

Author(s):

Barbara Szymankiewicz-Rak ◽

Jörg Mey ◽

Solon Thanos

Keyword(s):

Retinal Ganglion Cells ◽

Axonal Regeneration ◽

Ganglion Cells ◽

Retinal Ganglion

Download Full-text

Pathways of regenerated retinotectal axons in goldfish

Development ◽

10.1242/dev.93.1.1 ◽

1986 ◽

Vol 93 (1) ◽

pp. 1-28

Author(s):

Claudia A. O. Stuermer

Keyword(s):

Optic Nerve ◽

Retinal Ganglion Cells ◽

Normal Development ◽

Ganglion Cells ◽

Optic Tract ◽

Spatiotemporal Pattern ◽

Retinal Ganglion ◽

Retinal Axons ◽

Age Related ◽

Regenerated Fibres

This study investigates the order of regenerating retinal axons in the goldfish. The spatiotemporal pattern of axon regrowth was assessed by applying horseradish peroxidase (HRP) to regenerating axons in the optic tract at various times after optic nerve section and by analysing the distribution of retrogradely labelled ganglion cells in retina. At all regeneration stages labelled ganglion cells were widely distributed over the retina. There was no hint that axons from central (older) ganglion cells might regrow earlier, and peripheral (younger) ganglion cells later, as occurs in normal development. The absence of an age-related ordering in the regenerated optic nerve was demonstrated by labelling a few axon bundles intraorbitally with HRP (Easter, Rusoff & Kish, 1981) caudal to the previous cut. The retrogradely labelled cells in retina were randomly distributed in regenerates andnot clustered in annuli as in normals. Tracing regenerating axons which were stained anterogradelyfrom intraretinal HRP applications or retrogradely from single labelled tectal fascicles illustrated the fact that the regenerating axons coursed in abnormal routes in the optic nerve and tract. On the surface of the tectum regenerated fibres re-established a fascicle fan. The retinal origin of tectal fascicles was assessed by labelling individual peripheral, intermediate and rostral fascicles with HRP. The retrogradely labelled ganglion cells in the retina were often more widely distributed than in normals, but were mostly found in peripheral, intermediate and central retina, respectively. The order of fibre departure from each tectal fascicle was revealed by placing HRP either on the fascicle's proximal or on its distal half. With proximal labelling sites labelled ganglion cells were found in the temporal and nasal retina, and with distal labelling sites labelled ganglion cells were confined to nasal retina only. Further, the axonal trajectories of anterogradely labelled dorsotemporal retinal ganglion cells were compared to those of dorsonasal retinal ganglion cells in tectal whole mounts. Dorsotemporal axons were confined to the rostral tectal half, whereas dorsonasal axons followed fascicular routes into the fascicles' distal end and reached into caudal tectum. This suggests that the fibres exited along their fascicle's course in a temporonasal sequence. Thus in the tectum, fibres in fascicles restore a gross spatial and age-related order and tend to follow their normal temporonasal sequence of exit.

Download Full-text