FCCP induced mitochondrial depolarization in SH-SY5Y neuroblastoma cells transfected with G93A exhibits reduced peak fluorescence amplitude. A) A CCD imaging photomicrograph series showing [Ca2+]i in 7–8 cells before drug application (0.0s), after peak 2 μM FCCP challenge for 3 min, and after FCCP wash in WT (a-c) and G93A (d-f) transfected SH-SY5Y neuroblastoma cells. B) A representative figure of [Ca2+]i fluorescence intensity in 6 SH-SY5Y neuroblastoma cells transfected with WT after FCCP application. FCCP (2 μM) induced a fast, transient elevation in [Ca2+]i and a fast recovery to baseline. C) In G93A transfected SH-SY5Y neuroblastoma cells, FCCP induced a transient elevation in [Ca2+]i fluorescence intensity that was lower in magnitude, followed by a plateau for 1 min, and a delayed recovery to baseline. D) A bar diagram to illustrate the reduction of the sustained Ca2+ response in G93A transfected SH-SY5Y neuroblastoma cells (F/F0 = 0.0948 ± 0.0223; N = 5, n = 23) compared to WT transfected SH-SY5Y cells (F/F0 = 0.1766 ± 0.0362; N = 3, n = 17). Values represent means ± SD, **p < 0.001, scale bar = 10 μm. N = Number of experiments; n = Number of cells.