Ultrastructure of senile plaque using thick sections in the brain with Alzheimer's disease.

The subjects used in the present study consisted of 8 cases with Alzheimer's disease. Senile plaques which seemed to have no relation with the capillaries were examined in thick serial sections (3,000-5,000 A) by electron microscope. The results obtained were as follows: All of those senile plaques had amyloid angiopathy with amyloid fibrils and these amyloid fibrils formed the main elements of senile plaques. From these findings, it was confirmed that the amyloid fibrils in all plaques are produced from the capillaries.