Fig. 5

Aβ plaques cause spine loss and shaft atrophy in the distal segments of dendrites passing through plaques a. Confocal image of YFP labeled dendrites passing through and near Aβ plaques in the fixed brain slice of PSAPP mice crossed with Thy1 YFP H-line mice. Aβ plaques were labeled with Congo red (red). A yellow fluorescent protein-labeled dendrite (green) showed a significant reduction in spine density and dendritic diameter after entering the plaque. Scale bar, 20 μm. b. Upper panel shows the dendritic branch passing through the plaque in dashed area in a. Bottom panel shows the quantification of spine density (orange curve) and shaft diameter (blue curve) in every 20 μm long of dendritic segments, ranging from 0 to 80 μm from plaque border. c. Distal segments of dendrites passing through Aβ plaques showed reduced spine density and shaft diameter compared to proximal segments. (n = 22 dendrites from 4 mice, **P < 0.01, student t-test). d. Spine density and shaft diameter of dendrites located greater than 30 μm away from plaque deposits showed no difference in the proximal and distal segments (n = 22 dendrites from 4 mice, P > 0.05, student t-test)