BACKROUND: Studies suggest that hippocampal neurons may be more vulnerable to oxida-tive
stress than cortical cells. Since disturbed ATP-metabolism may be involved in such
a dif-ferential vulnerability of neurons, we here evaluated the effects of hydrogen
peroxide (H2O2-) induced oxidative stress on neuronal energy metabolism in different
neuronal systems. Methods: Using primary cortical and hippocampal neurons as well as immortalized hippo-campal
HT22 cells, we determined intracellular ATP levels and accompanying cell death after
oxidative challenge with H2O2. Furthermore, the effects of a long-time incubation
with H2O2 on the viability of HT22 cells were evaluated with a modified MTT-reduction
assay. Results: H2O2-incubation lead to decreased intracellular ATP levels in a dose- and time-dependent
manner in all neuronal cell systems tested. These effects were pronounced in pri-mary
hippocampal neurons and less detectable in HT22 cells. However, even long-time incu-bation
with comparable H2O2 concentrations did not obligatory lead to cell death in the MTT
assay. Conclusions: Our data underline that H2O2-treatment is able to disturb intracellular en-ergy metabolism
especially in primary hippocampal neurons. Decreased ATP levels do not obligatory
induce cell death but may explain the selective neuronal vulnerability.