HISTOPATHOLOGY OF THE SUBSTANTIA-NIGRA IN ALZHEIMERS-DISEASE

Histopathologic examination of the pars compacta of the substantia nig ra of 17 patients with Alzheimer's disease showed Lewy bodies in six, neurofibrillary tangles in another sis and only histologic changes tha t did not differ from age-matched controls in five patients, Four of t he six patients with nigral Lewy bodies showed severe loss of neural c ell bodies, reactive astrocytosis, gliosis and neuromelanin in macroph ages and in the neuropile. By contrast, the loss of neuronal cell bodi es in our patients without nigral Lewy bodies regardless of whether or not they also had nigral neurofibrillary tangles was no greater than what we observed in our age-matched controls. Quantitative cell counts confirmed our histopathologic estimates of neuronal loss. Our study a nd the findings of others show that the subutantia nigra is often abno rmal in Alzheimer's disease and that the abnormalities are rarely seve re without nigral Lewy bodies.