Fig. 5

Decreased pinceau synapse size and phosphorylated neurofilament in Purkinje cells is associated with axonal swellings after traumatic brain injury. a, b Disrupted pinceau synapses in the cerebellum following cFPI. a Confocal images showing co- labelling of calbindin (red) and parvalbumin (green) in the cerebellum of sham and cFPI mice at 2, 7 and 30 dpi, scale bar 10 μm. White arrowheads indicate pinceau width. b Quantification of pinceau width (μm) in the cerebellum of sham and cFPI mice at 2, 7 and 30 dpi (****P < 0.0001; Kruskal–Wallis followed by Dunn’s post hoc test). c Confocal images showing triple labelling of pNF-H (green), MBP (red), and calbindin (grey) of Purkinje cells in sham and cFPI mice at 7dpi. Fluorescence intensity profiles of pNF-H (green) expression in the PCL of sham-injured and cFPI mice cerebellum at 7dpi. d Morphological changes in calbindin-expressing Purkinje cells axons, including axonal swellings and thickening, in the brain- injured animals as compared to sham-injured controls at 7dpi. Confocal pictures are inverted into grey scale. Scale bars 10 μm in c and d. ML: molecular layer, PCL: Purkinje cell layer, GL: granular layer. pNF-H: phosphorylated neurofilament-heavy, MBP: myelin basic protein