Size of neocortical neurons in control subjects and in Alzheimer's disease

The aim of the present study was to estimate mean neuronal volume and absol ute size distributions of the neocortical neurons in brains from controls a nd AD patients using stereological methods based on unbiased principles to determine whether changes in absolute cell size are part of the neuropathol ogical pattern of Alzheimer's disease. The neocortex of S patients with Alz heimer's disease (PID), mean age 81.1 (68-94) y was compared with 9 nondeme nted controls: mean age 80.9 (65-101) y. The brains came from Johns Hopkins University Hospital (JHUH) in Baltimore, USA, the Netherlands Brain Bank ( NBB), and from a large brain repository in Denmark, The rotator method was used to obtain an estimate of cell volumes providing absolute size distribu tions of the volume of both cell perikaryon and cell nuclei. The geometric mean volume of cell nuclei in neocortical neurons was 328 mum(3) (interindi vidual CV = 0.15) in the Alzheimer group compared with 277 mum(3) (interind ividual CV = 0.17) in controls which was a statistically significant increa se (P = 0.049). The perikaryal volume was 1117 mum(3) in the Alzheimer grou p compared with 999 mum(3) in controls which was a nonsignificant differenc e (P = 0.2.0). There was a highly significant correlation between the nucle ar and perikaryal volumes in ah individuals. The average slope of the regre ssion lines was significantly higher in the Alzheimer patients than in the controls, illustrating that nuclear hypertrophy was more pronounced in the largest neurons.