RESUMO
Neuronal cell death is an important phenomenon involving many biochemical pathways. This degenerative event has been studied to understand how the cells activate the mechanisms that lead to self-destruction. Target cells and afferent cells play a relevant role in the regulation of natural cell death. We studied the effect of veratridine (1.5, 3.0, 4.5 and 6.0 muM) on the survival of neonatal rat retinal ganglion cells in vitro. Veratridine (3.0 muM), a well-known depolarizing agent that opens the Na+ channel, promoted a two-fold increase in the survival of retinal ganglion cells kept in culture for 48 h. This effect was dose-dependent and was blocked by 1.0 muM tetrodotoxin (a classical voltage-dependent Na+ channel blocker) and 3.0 muM flunarizine (a Na+ and Ca2+ channel blocker). These results indicate that electrical activity is also important for the maintenance of retinal ganglion cell survival in vitro.