Intraretinal neurotrophic activity prevents the degeneration of ganglion cells in retinal explants

The degeneration of ganglion cells was studied in neural retina explanted from the eyes of newborn rats. The ganglion cells were detected by the presence of retrogradely transported horseradish peroxidase injected into the superior colliculus. The time course of cell death among the axotomized ganglion cells in the explants was similar to that found in vivo after axotomy in neonatal rats. The effect of culture media conditioned with retinal cells from either newborn rats or chick embryos was tested on the survival of ganglion cells in the explants. Both conditioned media increased 2- to 3-fold the survival of rat retinal ganglion cells after 2 days in culture. The data show that soluble trophic factors released by retinae of distinct species can influence the survival of ganglion cells within their histotypic microenvironment.