Potential Roles for Nicotinic Acetylcholine Receptors in Parkinson’s and Alzheimer’s

Nicotinic acetylcholine receptors (nAChRs) exist as a diverse family of subtypes composed of different subunit combinations. They play many important physiological roles, and have been implicated in nicotine dependence and in a variety of neuropsychiatric conditions. Here I review the cholinergic hypotheses of Alzheimer’s and Parkinson’s diseases. I provide an overview of evidence for changes in numbers of nAChR¬like binding and immunoreactive sites in both Parkinson’s and Alzheimer ’s diseases, concerning apparent neuroprotective effects of nicotinic ligands in animal or cell culture models of those neurodegenerative disorders, and regarding therapeutic promise of nicotine and its analogs. A perspective will be presented about factors that warrant consideration in understanding possible etiopathological roles of nAChR in Alzheimer’s and Parkinson’s diseases and in prospective nicotinic pharmacotherapy.