Nicotinic and muscarinic cholinergic receptors in Alzheimer's disease and related disorders.

Alzheimer's disease (AD) and Parkinson's disease (PD) and to a lesser extent progressive supranuclear palsy are characterized by dysfunction of the cholinergic basal forebrain neurons which send projections to cortex and other areas of the telencephalon. In this paper we demonstrate that this cholinergic dysfunction is associated with consistent reductions in density of cortical nicotinic but not muscarinic cholinergic receptors in these disorders. These cholinergic abnormalities are not found in Huntington's disease.