RESUMO
INTRODUCTION AND OBJECTIVES: Retina is a privileged tissue to study the central nervous system (CNS) due to the disposition of different cell types and synaptic plexus. Moreover, the retina and the optic nerve are accessible for manipulation and surgery. Neuronal consequences of axotomy have been widely studied in this portion of the CNS. This paper offers a brief review of the morphological changes experienced by axotomized cells. We show these consequences in retinal ganglion cells (RGCs) injured by optic nerve section. DEVELOPMENT: Neurons transmit information to other cells through their axons; by cutting the axon not only the synaptic transmission is interrupted, but cell death is induced in axotomized neurons. In many cases degeneration of pre and postsynaptic neurons is also triggered. However, in the retinal model, some RGCs are able to survive to axotomy; they experience profound changes trying to adapt to a new situation. Such changes have been observed in labeled axotomized cells. CONCLUSION: Knowledge of the qualitative and quantitative changes after injury, as well as the determination of no return point in the evolution of the lesion are aspects that must be known before to start a repairing therapy of the function.
