Cortical distribution of neurofibrillary tangles in Alzheimer's disease matches the pattern of neurons that retain their capacity of plastic remodelling in the adult brain
Section snippets
Cases
Brains were obtained from 64 patients with AD and from 61 control patients. The profile of cases is summarized in Table 1. The clinical diagnosis of AD was based on the occurrence of significant intellectual dysfunction, i.e. the presence of deficits in at least four aspects of cognitive and social behaviour. Other causes of dementia were excluded by medical, psychiatric and paraclinical examination (Diagnostic and Statistical Manual of Mental Disorders, DSM-IIIR, American Psychiatric
Dendritic remodelling of pyramidal neurons
To obtain a measure of structural neuronal plasticity in the adult brain, changes in total length of apical and basal dendrites of pyramidal neurons and their degree of ramification was analysed in 12 cortical areas. Data are summarized in Fig. 1, Fig. 2, Table 2, averaged for the following five groups: (i) adult controls, (ii) senior controls, (iii) elderly controls, (iv) AD cases without ApoE epsilon 4 allele and (v) AD cases carrying one or two ApoE epsilon 4 alleles. Fig. 3 illustrates the
Regional differences in neuronal plasticity
The results of the present study demonstrate a regionally different structural plasticity in the cerebral cortex of the human brain during ageing. These observations are in agreement with a variety of previous studies on rodent, monkey and human brain that have been reported on marked regional differences in neuronal plasticity in the ageing brain as measured by the dendritic extent (for review see [28]).
A continued age-related net dendritic growth has been described in layer II pyramidal
Conclusion
It is tempting to speculate that general differences in the dynamics of structural organization of both subcortical and cortical areas might be related to the function which this brain areas subserves. Against the background of this hypothesis, it can be predicted that primary sensory and motor areas should display a higher degree of structural stability than limbic, paralimbic and associative areas that are involved in the processing and storage of information. It appears that some principles
Acknowledgements
This study was supported by the Bundesministerium für Bildung, Forschung und Technologie (BMBF), Interdisciplinary Centre for Clinical Research at the University of Leipzig (01KS9504, Project C1).
References (92)
- et al.
Increased expression and subcellular translocation of the mitogen-activated protein kinase kinase and mitogen-activated protein kinase in Alzheimer's disease
Neuroscience
(1995) - et al.
A membrane phosphoprotein associated with neuronal development, axonal regeneration, phospholipid metabolism, and synaptic plasticity
Trends Neurosci.
(1987) - et al.
A topographical study of senile plaques and neurofibrillary tangles in the hippocampi of patients with Alzheimer's Disease and cognitively impaired patients with schizophrenia
Psych. Res.
(1993) - et al.
Stability of dendrites in cortical barrels of C57B1/6N mice between 4 and 45 months
Neurobiol. Aging
(1986) - et al.
Neuron numbers and dendritic extent in normal aging and Alzheimer's disease
Neurobiol. Aging
(1987) - et al.
Age-related changes in prefrontal cortex of Macaca mulatta: quantitative analysis of dendritic branching patterns
Expl Neurol.
(1980) - et al.
The role of cortical connectivity in Alzheimer's disease pathogenesis: a review and model system
Neurobiol. Aging
(1993) The influence of post-mortem fixation delay on the reliability of the Golgi silver impregnation
Brain Res.
(1983)- et al.
The cortex of the primary auditory area in Alzheimer's disease
Brain Res.
(1986) Region-specific stability of dendritic extent in normal human aging and regression in Alzheimer's disease. II. Subiculum
Brain Res.
(1991)