Figure 2.

Effect of human PS1 wt overexpression on in vitro NMDA-induced neurotoxicity. Primary cerebellar neurons from wt mice (open bars) or human PS1 wt overexpressing mice (filled bars) were exposed to increasing concentrations of NMDA, as indicated. Cell death was measured by intravital staining with fluorescein diacetate and propidium iodide and was expressed as the percentage of dead cells over total cell number. Where indicated, MK-801 was added to the culture media 10 min before NMDA. Values are expressed as mean and confidence limits and are from nine separate cell preparations with each point run at least in quintuplicate. (Inset) Representative Western blot analysis of PS1 protein levels in cerebellar extracts from wt mice and mice overexpressing human wt (PS1 wt) or mutated (L286V) PS1. The C-terminal fragment of both human (h) and mouse (m) PS1 protein was detected with an anti-PS1 antibody. The calculated apparent molecular mass was 21 kDa and 20 kDa for human and mouse PS1 fragments, respectively.