Pathways of regenerated retinotectal axons in goldfish. I. Optic nerve, tract and tectal fascicle layer.

摘要: This study investigates the order of regenerating retinal axons in goldfish. The spatiotemporal pattern axon regrowth was assessed by applying horseradish peroxidase (HRP) to optic tract at various times after nerve section and analysing distribution retrogradely labelled ganglion cells retina. At all regeneration stages were widely distributed over There no hint that from central (older) might regrow earlier, peripheral (younger) later, as occurs normal development. absence an age-related ordering regenerated demonstrated labelling a few bundles intraorbitally with HRP (Easter, Rusoff & Kish, 1981) caudal previous cut. retina randomly regenerates andnot clustered annuli normals. Tracing which stained anterogradelyfrom intraretinal applications or single tectal fascicles illustrated fact coursed abnormal routes tract. On surface tectum fibres re-established fascicle fan. origin individual peripheral, intermediate rostral HRP. often more than normals, but mostly found retina, respectively. fibre departure each revealed placing either on fascicle9s proximal its distal half. With sites temporal nasal confined only. Further, axonal trajectories anterogradely dorsotemporal compared those dorsonasal whole mounts. Dorsotemporal half, whereas followed fascicular into fascicles9 end reached tectum. suggests exited along their course temporonasal sequence. Thus tectum, restore gross spatial tend follow sequence exit.