Neuronal and extraneuronal nicotinic acetylcholine receptors

Neuronal nicotinic acetylcholine receptors (nAChRs) belong to a super-family of Cys-loop ligand-gated ion channels that respond to endogenous acetylcholine (ACh) or other cholinergic ligands. These receptors are also the targets of drugs such as nicotine (the main addictive agent delivered by cigarette smoke) and are involved in a variety of physiological and pathophysiological processes. Numerous studies have shown that the expression and/or function of nAChRs is compromised in many neurological and psychiatric diseases. Furthermore, recent studies have shown that neuronal nAChRs are found in a large number of non-neuronal cell types including endothelial cells, glia, immune cells, lung epithelia and cancer cells where they regulate cell differentiation, proliferation and inflammatory responses. The aim of this review is to describe the most recent findings concerning the structure and function of native nAChRs inside and outside the nervous system.