Figure 4.

Immature Dcx⁺ neurons are selectively vulnerable to mitochondrial inhibition. A, Cultures treated with antimycin A (2 μm for 16 h) stained with an immature neuron marker Dcx (red) and a marker for more mature neurons MAP2 (green). Cell nuclei are counterstained with DAPI (blue). The cultures were stained after 16 h of antimycin A treatment, compared with the 24 h time point used for quantification to capture the residual Dcx staining that is essentially gone after 24 h. Cells expressing both Dcx and MAP2 cell markers (arrows) showed better preserved morphology and Dcx staining compared with Dcx-only expressing cells (arrowheads). Scale bar, 50 μm. B, Fractions of Dcx⁺ and MAP2⁺ cell (relative to the total cell number) in control- and antimycin A (2 μm, 24 h)-treated cultures. The data are representative of three independent experiments with at least 700 cells per condition in each experiment. Shown are mean ± SEM. **p < 0.01 compared with control MAP2; ***p < 0.001 compared with control Dcx. C, Only a small fraction of Dcx⁺ cells (green) were proliferating after 8–9 d of differentiation, as demonstrated by colabeling with BrdU (red). The fraction of proliferating BrdU cells was not significantly changed by 24 h antimycin A treatment.