Fig. 5
From: Mitochondrial dysfunction within the synapses of substantia nigra neurons in Parkinson’s disease
Analysis of empty synapses and respiratory deficiencies within the soma of SN neurons. Using triple immunofluorescence synapses containing no mitochondrial signal were detected. Within a population synapses which contained mitochondria (white, open arrowhead) were found alongside those with no mitochondria (yellow, closed arrowhead) (a). Surfaces for both types of synapse can be created (b) and when these surfaces are mapped onto the signal for porin it becomes clear that these empty synapses are deficient for porin (c) compared to their counterparts (d). e The percentage of synapses that were devoid of mitochondria was then calculated in each group of patients, there was a significant reduction in the number of these synapses in PD and DLB (***p = ≤0.001). Using quadruple immunofluorescence for TH, COXI, NDUFB8 and porin, the percentage of neuronal cell bodies within the SN that were deficient for NDUFB8 (f) or COXI (g) could be calculated. The number of cell bodies which were deficient for these proteins was found to be increased in PD and DLB, but not significantly. Scale bar represents 3 µm. Kruskal–Wallis one-way ANOVAs were performed with Dunn’s multiple comparison testing to ascertain statistical significance. Error bars represent s.e.m
