Ultrastructural changes of blood vessels in the cerebral cortex in Alzheimer's disease.

Several parts of the cerebral cortices in five brains from patients with Alzheimer's disease were examined by light and electron microscopes. The results obtained are as follows: The initial change of the cerebral cortex in the brain occurred in the small blood vessel and capillary. The endothelial cell of the blood vessel fell into a degenerated state with swelling of the vascular feet and astroglial cells. The change in a great number of nerve cells and their processes diffusely observed in the cortices were nonspecific and could be due to primary vascular degeneration. Severe dementia in Alzheimer's disease seemed to be well explained by the histopathological findings of diffusely destroyed nerve cells and their processes. From this, Alzheimer's disease can be speculated to be a disease caused by progressive capillary degeneration.