["To investigate whether intracellular amyloid β (iAβ) induces toxicity in wild type (WT) and APP/PS1 mice, a mouse model of Alzheimer's disease.", 'Different forms of Aβ aggregates were microinjected into cultured WT or APP/PS1 mouse hippocampal neurons. TUNEL staining was performed to examine neuronal cell death. Reactive oxidative species (ROS) were measured by MitoSOXRed mitochondrial superoxide indicator.', 'Crude, monomer and protofibril Aβ induced more toxicity in APP/PS1 neurons than in WT neurons. ROS are involved in mediating the vulnerability of APP/PS1 neurons to iAβ toxicity.'] Do reactive oxidative species enhance amyloid toxicity in APP/PS1 mouse neurons?