Aging changes in the human brain: a histochemical and immunohistochemical study.

There are very few studies on neuropathological changes of aging in the Indian population. In the present study, the incidence of aging changes in 20 non-demented elderly humans above the age of 55 years were observed. The incidence of neurofibrillary tangles (NFT) increased from 20% in 50-55-year-olds to 80% in 55-year-olds and over. Senile plaques (SP) increased from 20% in 50-55-year-olds to 80% in 55-60-year-olds and 40% in 60-year-olds and over. The results of immunohistochemistry to label the NFT (Tau) and SP (beta-amyloid) were comparable to the Bielchowsky's modified silver methanamine method. The incidence of age related changes and their antigenic character in the limited sample studied from north-west India appear to be comparable to those from the southern part of India and Western hemisphere.