Fig. 5.

NanoSIMS analysis of ¹³C enrichment in specific organelles within the cell body of nigral neurons (control hemisphere). a Representative SEM image of a large neuronal cell body located in the SNpc allowed to identify three types of organelles, the mitochondria (m), the Golgi apparatus (g) and lysosomes (ly). b SEM-based segmentation of compartments and organelles in the cell body; Cy: cytoplasm; Nu: nucleus; n: nucleolus. c Corresponding map of ¹³C enrichment. Note the presence of both ¹³C-rich lysosomes (ly⁺) and ¹³C-poor lysosomes (ly⁻) within the same neuronal cell body. d ¹³C enrichment in Golgi, mitochondria and lysosomes, as compared to the cytoplasm, measured at the end of the pulse with ¹³C-labeled glucose (48 h time point) and after the chase period (96 h time point). Note the significant decrease in ¹³C enrichment in the Golgi and mitochondria. In contrast, ¹³C enrichment in lysosomes is highly variable and does not significantly decrease over the chase period. The thick lines in the violin plots represent the median and the thin lines the upper and lower quartiles. The number of organelles analyzed is indicated at the bottom of the histogram bar. 48 h: N = 11 neurons from 2 rats; 96 h: N = 12 neurons from 3 rats. Statistical analysis: Mann–Whitney two-tailed test; ns = not significant; ****P < 0.0001. Scale bar: 2 µm