Bilateral Symmetry of Cholinergic Deficits in Alzheimer's Disease

The specific activities of the cholinergic enzymes, choline acetyltransferase and acetylcholinesterase, as well as the density of muscarinic binding sites, were determined in five corresponding left and right regions of 16 brains obtained at autopsy from patients with histologically confirmed Alzheimer's disease. While a significant proportion of the individual specimens exhibited left-right asymmetries in cholinergic deficits, bilateral symmetry was the rule for frontal and temporal cortex, basal nucleus, and the prosubiculum of the hippocampus. In contrast to these four regions, left-right asymmetries in choline acetyltransferase activity and muscarinic receptor density appeared to be typical in the entorhinal cortex of the hippocampus.