Regenerative capacity of retinal axons in the cat, rabbit, and guinea pig

Long-term signs of axonal regeneration were observed in the adult cat, rabbit, and guinea pig retina to follow mechanical or thermal lesions. The axons of surviving ganglion cells displayed signs of growth beginning at the border of the lesions: multiple bifurcations, changes of caliber, and unoriented random course of the fibers. Inspection of the fiber course and retrograde filling with horseradish peroxidase showed that these attempts of regeneration were not successful in terms of reconnection to the brain. None of these axonal changes occurred after early postnatal lesions. The capacity for long-survival regenerative processes after axotomy begins 20 to 50 days after birth in the developing cat retina.