Chapter 37 Selective vulnerability of corticocortical and hippocampal circuits in aging and Alzheimer's disease

doi:10.1016/S0079-6123(02)36039-4

Progress in Brain Research

Volume 136, 2002, Pages 467-486

https://doi.org/10.1016/S0079-6123(02)36039-4 Get rights and content

Abstract

Alzheimer's disease (AD), a classic neurodegenerative disorder, is characterized by extensive yet selective neuron death in the neocortex and hippocampus that leads to dramatic decline in cognitive abilities and memory. Crucial subsets of pyramidal cells and their projections are particularly vulnerable. A more modest disruption of memory occurs often in normal aging, yeat such functional decline does not appear to be accompanied by significant neuron death. However, the same circuits that are devastated through degeneration in AD are vulnerable to sublethal age-related biochemical and morphologic shifts that alter synaptic transmission, and thereby impair function. For example, in the monkey neocortex, pyramidal cells that are homologous to those that degenerate in AD do not degenerate with aging, yet they lose spines, suggesting that an age-related synaptic disruption has occurred. Such age-related synaptic alterations have also been reported in hippocampus. For example, NMDA receptors are decreased in certain hippocampal circuits with aging. NMDA receptors are also responsive to circulating estrogen levels, thus interactions between reproductive senescence and brain aging may also affect excitatory synaptic transmission in the hippocampus. Thus, the aging synapse may be the key to age-related memory decline, wherease neuron death is the more prominent and problematic culprit in AD.

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Chapter 37 Selective vulnerability of corticocortical and hippocampal circuits in aging and Alzheimer's disease

Abstract

Neurosci. Lett.

Brain Res.

Neurobiol. Aging

Neurosci. Lett.

Brain Res.

Neurobiol. Aging

Exp. Neurol.

Neurosci. Lett.

J. Chem. Neuroanat.

Adv. Cell Aging Gerontol.

Exp. Neurol.

Cell

Neuroscience

Brain Res.

Prog. Neurobiol.

Neuroscience

Exp. Neurol.

Neurobiol. Aging

Neurobiol. Aging

Horm. Behav.

Different modes of hippocampal plasticity in response to estrogen in young and aged female rats

Hippocampal dependent learning ability correlates with N-methyl-d-aspartate (NMDA) receptor levels in CA3 neurons of young and aged rats

J. Comp. Neurol.

Cognitive and neurobiologic markers of early Alzheimer's disease

Neuropathologic changes in the temporal pole in Alzheimer's disease and Pick's disease

Arch. Neurol.

The topographical and neuroanatomical distribution of neurofibrillary tangles and neuritic plaques in the cerebral cortex of patients with Alzheimer's disease

Cereb Cortex

Pattern in the laminar origin of corticocortical connections

J. Comp. Neurol.

Multistability of cognitive maps in the hippocampus of old rats

Nature

Regional distribution of neurofibrillary tangles and senile plaques in the cerebral cortex of elderly patients: a quantitative evaluation of a one-year autopsy population from a geriatric hospital

Cereb. Cortex

Molecular pathology of Alzheimer amyloid and neurofibrillary tangles

Semin. Neurosci.

A monoclonal antibody to neurofilament protein (SMI-32) labels a subpopulation of pyramidal neurons in the human and monkey neocortex

J. Comp. Neurol.

The endocrine control of ovulation

Sci. Prog.

The use of animal models to study the effects of aging on cognition

Annu. Rev. Psychol.

Circuit-specific alterations of N-methyl-d-aspartate subunit 1 in the dentate gyrus of aged monkeys

Proc. Natl. Acad. Sci. USA

Differential regulation of NMDAR1 mRNA and protein by estradiol in the rat hippocampus

J. Neurosci.

Topography of cognition: parallel distributed networks in primate association cortex

Annu. Rev. Neurosci.

Profound loss of layer II entorhinal cortex neurons occurs in very mild Alzheimer's disease

J. Neurosci.

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Ann. Neurol.

Gonadal steroids regulate dendritic spine density in hippocampal pyramidal cells in adulthood

J. Neurosci.

Fractal analysis of aggregates of nonuniformly sized particles: an application to macaque monkey cortical pyramidal neurons

Fractals