PDAPP; YFP double transgenic mice: A tool to study amyloid-β associated changes in axonal, dendritic, and synaptic structures

• Published in: Journal of comparative neurology (1911) 2003-02, Vol.456 (4), p.375-383
• Main Authors: Brendza, Robert P., O'Brien, Cara, Simmons, Kelly, McKeel, Daniel W., Bales, Kelly R., Paul, Steven M., Olney, John W., Sanes, Joshua R., Holtzman, David M.
• Format: Article
• Language: English
• Subjects: Alzheimer Disease - metabolism; Alzheimer Disease - pathology; Alzheimer's disease; Amyloid beta-Peptides - metabolism; Amyloid beta-Protein Precursor - genetics; Animals; Bacterial Proteins - genetics; Brain - metabolism; Brain - pathology; Dendrites - pathology; Disease Models, Animal; fluorescent protein; Immunohistochemistry; Luminescent Proteins - genetics; Mice; Mice, Transgenic; Microscopy, Electron; Neurites - pathology; neuritic dystrophy; Neurons - metabolism; Neurons - pathology; Presynaptic Terminals - pathology; silver stain; Silver Staining; Synaptic Vesicles - pathology
• ISSN: 0021-9967; 1096-9861
• DOI: 10.1002/cne.10536

Neuritic plaques are one of the stereotypical hallmarks of Alzheimer's disease (AD) pathology. These structures are composed of extracellular accumulations of fibrillar forms of the amyloid‐β peptide (Aβ), a variety of other plaque‐associated proteins, activated glial cells, and degenerating nerve processes. To study the neuritic toxicity of different structural forms of Aβ in the context of regional connectivity and the entire cell, we crossed PDAPP transgenic (Tg) mice, a model with AD‐like pathology, to Tg mice that stably express yellow fluorescent protein (YFP) in a subset of neurons in the brain. In PDAPP; YFP double Tg mice, markedly enlarged YFP‐labeled axonal and dendritic varicosities were associated with fibrillar Aβ deposits. These varicosities were absent in areas where there were nonfibrillar Aβ deposits. Interestingly, YFP‐labeled varicosities revealed changes that corresponded with changes seen with electron microscopy and the de Olmos silver staining technique. Other silver staining methods and immunohistochemical localization of phosphorylated neurofilaments or phosphorylated tau were unable to detect the majority of these dystrophic neurites. Some but not all synaptic vesicle markers accumulated abnormally in YFP‐labeled varicosities associated with neuritic plaques. In addition to the characterization of the effects of Aβ on axonal and dendritic structure, YFP‐labeled neurons in Tg mice should prove to be a valuable tool to interpret the localization patterns of other markers and for future studies examining the dynamics of axons and dendrites in a variety of disease conditions in living tissue both in vitro and in vivo. J. Comp. Neurol. 456:375–383, 2003. © 2003 Wiley‐Liss, Inc.