AUTOMATED DIFFERENTIAL CELL COUNTING ON A SECTOR OF THE NORMAL HUMAN HIPPOCAMPUS: THE INFLUENCE OF AGE

Abstract

The neurons and the glia of the human hippocampus are notoriously vulnerable in various pathological conditions including those linked to ageing. There may even be differences between the young and the old in the absence of manifest disease. Using an image analyzer, systematic measurements of cell numbers in the region of the Sommer (Hl) sector of the human hippocampus were made on postmortem tissue from 37 female and 49 male subjects aged between 15-96 yr. In 15 male and 15 female subjects both hemispheres were available for analysis so measurements were made on a total of 116 hemispheres. For each specimen the fresh volume of the hemisphere was measured and corrections subsequently made for changes in size which occurred during fixation, processing, mounting and staining. After all the correction factors were applied the number of nucleolated neurons fell by .apprx. 3.6% per decade (P < 0.0001). There was no significant age-related change in the number of glia. Marked individual variations were found.