Figure 2: Morphological analyses of mitochondria in striatal terminals.
From: Drp1 inhibition attenuates neurotoxicity and dopamine release deficits in vivo
(a) Electron microscopy (EM) shows the size and shape of mitochondria in the striatum ranging from small to highly elongated morphology. For ultrastructural analyses of mitochondria in striatal DA axonal terminals, immuno-EM was performed in coronal striatal sections from ~1-year-old Pink1+/+ (WT, b) and Pink1−/− (KO, c) littermates transduced with eGFP control, Drp1-K38A or Fis1. Arrows indicate tyrosine hydroxylase (TH)-positive axonal terminals containing mitochondria, whereas arrowheads indicate those in TH-negative structures. Quantitative measurements of mitochondria were expressed as perimeter (d). Data represent mean±s.e.m. of three animals with 50 clearly identifiable mitochondria (cristae and/or double membrane) randomly and blindly selected per mouse, grouped into different size bins and analysed using two-way analysis of variance (Bin <0.8 μm: genotype: F1,12=0.00, P=1.00; AAV constructs: F2,12=8.33, P<0.01; Bin 0.8–1.1 μm: genotype: F1,12=0.00, P=1.00; AAV constructs: F2,12=27.07, P<0.001; Bin 1.1–1.4 μm: genotype: F1,12=0.00, P=1.00; AAV constructs: F2,12=9.29, P<0.01; Bin 1.4–1.7 μm: genotype: F1,12=0.27, P=0.61; AAV constructs: F2,12=8.02, P<0.001; Bin >1.7 μm: genotype: F1,12=0.07, P=0.80; AAV constructs: F2,12=35.16, P<0.001). Pairwise comparison was performed using Newman–Keuls post-hoc test. *P<0.05 compared with the GFP group, #P<0.05 compared with the Fis1 group, respectively, within each genotype. Scale bars (a), 1 μm, (b,c), 400 nm.
