DENDRITIC CHANGES IN ALZHEIMERS-DISEASE AND FACTORS THAT MAY UNDERLIETHESE CHANGES

It seems likely that the Alzheimer disease (AD)-related dendritic chan ges addressed in this article are induced by two principally different processes. One process is linked to the plastic response associated w ith deafferentation, that is, long-lasting transneuronally induced reg ressive changes in dendritic geometry and structure. The other process is associated with severe alterations of the dendritic- and perikarya l cytoskeleton as seen in neurons with the neurofibrillary pathology o f AD, that is, the formation of paired helical filaments formed by hyp erphosphorylated microtubule-associated protein tau. As the developmen t of dendritic and cytoskeletal abnormalities are at least mediated by alterations in signal transduction. this article also reviews changes in signal pathways in AD. We also discuss transgenic approaches devel oped to model and understand cytoskeletal abnormalities. (C) 1998 Else vier Science Ltd. All rights reserved.