Muscarinic Acetylcholine Receptors

Abstract The five muscarinic acetylcholine receptors (M1–M5mAChRs) are prototypical members of the superfamily of G protein‐coupled receptors. The M1–M5mAChRs regulate an extraordinarily large number of central and peripheral functions. The first part of this chapter primarily focuses on how mAChRs function at a molecular level, the diversity of cellular responses following mAChR activation, and the mechanisms that are involved in regulating mAChR activity. The second part of this chapter summarizes recent results obtained with mutant mouse strains deficient in specific mAChR subtypes. These studies have led to a wealth of novel information about the physiological and pathophysiological roles of the individual mAChRs which may pave the way toward the development of novel, clinically useful muscarinic drugs.