Fig 2. Resistance to calcium-induced mPTP opening in response to Wnt3a.

(A) Representative images showing DIV10 hippocampal neurons treated with control media, recombinant Wnt3a protein (300 ng/ml) or pretreated 30 min with DKK1 (100 ng/mL) and coincubated with Wnt3a for 24 h and loaded with calcein-Co²⁺ to stain mitochondria. The fluorescence intensity decay of mitochondrial calcein corresponds to mPTP opening in response to 20 μM CaCl₂ exposure. Yellow rectangles indicate magnified regions. Scale bar, 8 μm. Close-up images are shown in black and white (x4 magnification) as well as pseudocoloured images. Intensity plots represent the fluorescence intensity profile of each magnified region. (B) Time-lapse quantification of the fluorescence intensity variations. The arrows indicate the addition of 20 and 100 μM CaCl₂. The results represent the analysis of 5–10 neurites from 2 neurons per experiment. (C) The graph represents the measurements of each condition after the addition of 20 μM CaCl₂ (140 s) of the experiment, normalized to the basal average registered previous to the stimulus. mPTP opening is visualized as a decay in the fluorescence. The graph shows the mean ± SEM of n = 3–5 independent experiments. Statistical analysis was performed using one-way ANOVA *p<0.05.