Granule cell apoptosis induced by overdose copper and ethanol is counterbalanced by co-induced cellular proliferation in rat dentate gyrus

Copper (Cu) is an essential element for life, however, is toxic at excessive doses, whereas exposure to ethanol (EtOH) has been known to cause morphological changes, degeneration and neuronal loss in central nervous system (CNS). In this study, the effect of overdose co-exposure to Cu and EtOH on dentate gyrus was investigated in rats. Analysis of apoptotic cell death on the basis of TdT-mediated dUTP nick end labeling (TUNEL) assay revealed that the rate of apoptosis was increased by 1.84 folds in treated group in comparison to that in controls (p 0.05). These results suggest that the apoptotic effect of overdose Cu and EtOH on granule cells of dentate gyrus may be counterbalanced by the co-induced cellular proliferation, thereby maintaining the total granule cell number unaltered. © 2005 Tohoku University Medical Press