Angiotensin II Immunoreactivity in the Human Striatum and Hippocampus of Elderly Controls and Patients with Senile Dementia of the Alzheimer Type and Multi-Infarct Dementia

Abstract

The distribution of angiotensin II (A II) immunoreactivity in the postmortem human corpus striatum was studied in control cases and in patients with senile dementia of the Alzheimer type (SDAT) and multi-infarct dementia (MID). Additionally A II immunoreactivity was examined in the hippocampus of control and SDAT patients. A II-immunopositive cellular structures found in the striatum were the large neurons and vesiculated fibers in the globus pallidus (GP), especially in the dorsal parts, and some aspiny neurons in the putamen. Changes in the cell morphology marked the neurons in the GP of SDAT patients. In the MID cases only a few A II-immunopositive fibers and no cell somata were present in the GP. An extracellular, perivascular A II-staining pattern, which was found only in 1 control case, was common to all SDAT and MID patients. A II-immunopositive cellular structures found in the hippocampus included distorted neuronal processes and vesiculated fibers, which were partly coexisting with neuritic plaques as shown by the double labeling with thioflavin. The perivascular A II staining was also observed in the hippocampus, which was more predominant in SDAT cases. The definition of these two A II-immunopositive cell types in human corpus striatum suggests that A II may be involved in local neuronal or projection pathways. Possibly A II participates in the development of cerebrovascular pathologies in elderly control and demented brains.