Cholinergic muscarinic binding by human lymphocytes: changes with aging, antagonist treatment, and senile dementia of the Alzheimer type.

In peripheral blood lymphocytes (mixed lymphocytes isolated on a Ficoll-Hypaque density gradient) derived from normal human subjects, cholinergic muscarinic binding capacity was found to increase with age. In contrast, lymphocytes derived from patients with "probable" senile dementia of the Alzheimer type (SDAT) exhibited a marked reduction in binding capacity. Treatment of these patients with antimuscarinic drugs was associated with increased muscarinic binding by lymphocytes. These results indicate that cholinergic muscarinic binding by peripheral blood lymphocytes may be useful in the study of alterations associated with aging and SDAT, as well as in evaluating changes induced by certain cholinergic drug treatments.