Cell Loss with Aging
There have been several techniques developed to determine the number of cells in the central nervous system. Probably the simplest and the most common technique has been the ocular micrometric method. This was originally used by Hammerberg in 1895 and while other techniques may be mentioned, it is at the present time the most consistent and dependable. It involves examination of tissue with the aid of a micrometer disc inserted into the ocular of a compound microscope. Cells which fall within the squares of the disc may then be counted and total counts made as well as graphs showing relative populations within any portion of the section. This is most useful in determining cell numbers within a brain stem nuclear structure since it is possible in serial section counting to obtain an impression of the cell population at any specific point. By examination in several planes, one may obtain a 3-dimensional impression of the nucleus, and to compare specific sites within the nucleus in a number of brain specimens when the nucleus is of similar size. Direct optical examination of tissue by the investigator also makes possible a differentiation of neurons from glial cells and discriminates fairly easily when there is an overlapping of cells.
KeywordsCerebral Cortex Purkinje Cell Aging Brain Senile Dementia Inferior Olive
Unable to display preview. Download preview PDF.
- Brody, H. Structural changes in the aging nervous system. In: Interdisciplinary Topics in Gerontology. (Ed. Blumenthal, H.), Karger, Basel/Munchen, 1970.Google Scholar
- DeLorenzi, E. Constenza numerica delle cellule del Purkinje in individui di varia eta. Bull, Soc. ital. biol. sper. 6:80–82, 1931.Google Scholar
- Economo, C. and Koskinas, G. Die Cytoarchitektonik der Hirnrinde des erwachsenen Menschen. Leipsig, 1925.Google Scholar
- Feldman, M. Dendritic changes in aging rat brain. In: Aging Brain and Senile Dementia. (Eds. K. Nandy and I. Sherwin), Plenum Press, New York, 1977.Google Scholar
- Hodge, C. F. Changes in ganglion cells from birth to senile death. Observations on man and honey bee. J. Physiol. 17:129–134, 1894.Google Scholar
- Hyden, H. The Neuron. In: The Cell. (Eds. J. Brachet and A.E. Mirsky), Academic Press, New York, 1960.Google Scholar
- Maleci, O. Sul rapporto numerico tra 1e cellule dei nuclei di origine e 1e fibre di nervi motor encefalici dell’uomo, con osservazioni sulle differenze qualitative delle dette fibre. Arch. Ital. Annt. Embriol. 35:559–583, 1936.Google Scholar
- Nurnberger, I. I. Direct enumeration of cells of the brain. In: Biology of Neuroglia. (Ed. Windle, W.F.), Charles C. Thomas, Springfield, 1958.Google Scholar
- Scheibel, M. E. and Scheibel, A.B. Differential changes with aging in old and new cortices. In: Aging Brain and Senile Dementia. (Eds. K. Nandy and I. Sherwin), Plenum Press, New York, 1977.Google Scholar
- Tomlinson, B. E. Some quantitative cerebral findings in normal and demented old people. In: Neurobiology of Aging. (Eds. R. O. Terry and S. Gershon), Raven Press, New York, 1976.Google Scholar
- Vijayashankar, N. and Brody, H. Neuronal population of human abducens nucleus. Anat. Record 169(2):447, 1971.Google Scholar
- Vijayashankar, N. and Brody, H. A study of aging in the human abducens nucleus. J. of Comp. Neurol., 1977a, in press. Vijayashankar, N. and Brody, H. Aging in the human brainstem: A study of the nucleus of the trochlear nerve. Acta Anatomica, 1977b, in press.Google Scholar