The effects of beta-amyloid isoforms on intracellular and mitochondrial calcium levels in bEnd.3 cells. Cells were incubated for 4 h (A,B), 24 h (C,D) and 48 h (E,F) with 10 μM of Aβ42, p-Aβ42 and iso-Aβ42. Flow cytometry was used to analyze changes in intracellular calcium (A,C,E) and mitochondrial calcium (B,D,F). All parameters were normalized to control. The values in the control samples were taken as 100%. The mean ± SD in 3 independent experiments in triplicates is shown in the figure. The statistical difference between experimental groups was analyzed by one-way analysis of variance using the post hoc Tukey test for multiple comparisons. *—p < 0.05, ** —p < 0.01 and ***—p < 0.001.