Full-length, synthetic Aβ 1–42 peptides (AβOs; American Peptide, Sunnyvale, CA) were prepared exactly according to the method of Lambert et al. (1998) (link) and applied to 11–13 DIV cells at a final concentration of 500 nM for 18 h. We use synthetic AβOs in our studies for the following reasons. First, they mimic the toxic properties of natural oligomers (brain or cell derived) as described previously (Jin et al., 2011 (link); Welzel et al., 2014 (link)). Second, unlike natural oligomers, synthetic AβOs can be detected by immunocytochemistry. Confirmation of AβO binding is crucial in our experiments because it varies considerably between neurons. Although they may not be identical to natural oligomers, synthetic AβOs are a tractable tool for investigating mechanisms of AD pathogenesis (Ferreira and Klein, 2011 (link)). After AβO or vehicle exposure, cells were incubated with 1 μM FK506 (Sigma-Aldrich, St. Louis, MO) or equivalent volumes of vehicle (ethanol) for 1–3 h before imaging of transport. For all VGCC inhibition experiments, cells were incubated with 100 μM conotoxin GVIA (Alomone Labs, Jerusalem, Israel), 50 μM agatoxin IVA (Alomone Labs), or 10 μM nimodipine (Tocris Bioscience, Bristol, United Kingdom) for 30 min before AβO treatments. For all RyR inhibition experiments, cells were incubated with 0.5 μM dantrolene (Sigma-Aldrich) for 1 h before AβO treatment.