Fig. 13

Assessment of synaptic and axonal ultrastructure using transmission electron microscopy. a. Table summarizing the pre- and post-synaptic parameters measured in the LBC1936 and AD brains at the EM level. Significant differences are highlighted in red. b. Representative electron micrographs from BA46 and EC from the LBC1936 and AD brains. Arrows point to the synapse from the pre-synapse. White arrow highlights an electron dense degenerating synapse. Mito = mitochondria, MVB = multi-vesicular body. c. Representative electron micrograph from the LBC1936 genu of the corpus callosum sample, showing axons cut in cross-section. d. Higher magnification of the boxed section in (c), showing how g-ratio is determined in each sample. The perimeter is draw around the internal axon cross-section (solid line) and divided by the perimeter of the axon + myelin cross-section (dashed line). G-ratio values from four white matter regions are found in the adjoining table