Circulating suppressing factor for the muscarinic acetylcholine receptor in patients with senile dementia of the Alzheimer type.

Abstract

Circulating suppressing factor for the binding of quinuclidinyl benzilate (QNB), an antagonist for the muscarinic acetylcholine receptor, to the synaptic membranes was evaluated in 48 patients with senile dementia of the Alzheimer type (SDAT), in 17 patients with the vascular type dementia (VTD) and in 11 nondemented elderly subjects (NE). The mean suppression rate on the binding in the SDAT group was significantly greater than that in the NE group, although that in the VTD group was similar to that in the NE group. Moreover, the percent QNB binding was significantly (p < 0.05) correlated with the score of the mini-mental state in the SDAT group. The circulating suppressing factor may participate in the pathogenesis of SDAT.