Changes in the regional brain histamine and histidine levels in postmortem brains of Alzheimer patients

Abstract

In postmortem brains of Alzheimer patients, statistically significant decreases in histamine levels were observed in the frontal (45%), temporal (20%), and occipital cortices (38%) and in the caudate nucleus (25%). Histidine levels were decreased in the frontal (15%), temporal (21%), and occipital cortices (30%) and in the caudate nucleus (25%); the decrease was statistically significant in the last two brain regions. Histamine was determined by the double isotope technique, and histidine was determined fluorometrically by a fluorescamine method. The data indicate that brain histamine regulation is altered in Alzheimer's disease.