Ultrastructural differences in pretangles between Alzheimer disease and corticobasal degeneration revealed by comparative light and electron microscopy

Table 2 Similarities and differences between AD-pretangle and CBD-pretangle

		AD		CBD
		Pretanle	NFT	Pretangle	Pick like inclusion
LM findings (confocal images)	Morphology	Granular	Fibrillary	Reticular	Round, frequent vacuoles
	Perinuclear accentuation	Occiasional	Occasional	None	None
	Size of neurons involved	Small- to large- sized	Small- to large- sized	Medium- to large-sized	Small-sized
EM findings	Density of tau filaments	Very sparse*1	Very dense*2	Sparse	Dense
	Arrangement of tau filaments	Irregular/regular (focal NFT formation*3)	Regular (NFT formation)	Irregular	Irregular
	Diameter of straight filaments	About 15 nm	About 15 nm	14-20 nm	About 15 nm
	PHF (a periodicity)	Occasional (about 80 nm)	Frequent (about 80 nm)	None	Occasional (130–180 nm)

IHC, immunohistochemistry; LM, light microscopy; EM, electron microscopy; PHF, paired helical filaments; *1, Density of straight tau filament is more sparse in AD-pretangles than in CBD-pretangles; *2, Density of tau filaments is more dense in AD-NFT than in Pick-like inclusions of CBD; *3, NFT, neurofibrillary tangle signifying a regularly and tightly arranged bundle of straight or paired helical filaments.

ISSN: 2051-5960