Memantine blocks AβO-induced neuronal CCR. (A) Primary cortical neurons were treated with AβOs with or without pretreatment with 10 μM memantine. Cells were then stained with antibodies to MAP2, NeuN, and cyclin D1 to identify CCR neurons. (B) Quantification of the immunofluorescence results and statistical analysis by one-way ANOVA. Error bars indicate S.E.M. Abbreviations: ANOVA, analysis of variance; AβO, amyloid-β oligomer; CCR, cell cycle reentry.