Topographic relationship between neurofibrillary change and acetylcholinesterase rich neurons in the upper brain stem of patients with senile dementia of the Alzheimer's type and Down's syndrome.

In order to establish the topographical relationship between neurofibrillary change and the distribution of cholinergic neurons, the upper brain stems were studied from nine cases of senile dementia of the Alzheimer's type (SDAT). For each case, the distribution of the neurofibrillary changes was recorded and compared with the distribution in five control patients of acetylcholinesterase-rich neurons as determined by enzyme histochemistry. The numbers and distribution of neurons with neurofibrillary change were also studied in five age-matched controls and in three individuals with Down's syndrome. The results indicate that, in contrast to that in control patients, the upper brain stem is heavily involved by neurofibrillary change in SDAT. Correlation of the distribution of neurofibrillary tangles in SDAT patients with the localization of acetylcholinesterase-rich neurons suggests that most of the cholinergic nuclei in the upper brain stem are affected in SDAT, but are not exclusively or predominantly involved. Most neurofibrillary tangles were found in noncholinergic nuclei such as the raphe nuclei and the locus ceruleus. The individuals with Down's syndrome showed a heavy involvement in the older cases, thus reinforcing the significance of Down's syndrome in defining the evolution of pathologic changes in Alzheimer's disease or SDAT.