Effect of resveratrol on the basal cellular Ca2+ level in control and parkin-mutant fibroblasts in the presence of thapsigargin (TG). Spectrofluorometric measurements of cytosolic (a) and mitochondrial (b) Ca2+ levels in control (open bar), and parkin-mutant (black bar) fibroblasts loaded, respectively, with Fluo-4AM and X-Rhod-1AM. The cells were exposed for 30 min to vehicle (DMSO) or 25 μM resveratrol (RSV). Where indicated, the cells were incubated for 30 min with 1 µM thapsigargin (TG) alone or co-incubated with resveratrol (RSV+TG). The values, expressed as nM, represent the means ± SEM from 3 independent experiments under each condition. The significance was determined by two-way ANOVA with Tukey post hoc; *, p ˂ 0.01; ****, p ˂ 0.0001. The statistical significance of Ca2+ level among DMSO and RSV treatments is presented in Figure 5 and omitted herein to streamline the figure. For more details, see Materials and Methods.