Nicotinic acetylcholine receptors (nAChRs) present as many different subtypes in the nervous and immune systems, muscles and on the cells of other organs. In the immune system,
inflammation is regulated via the vagus nerve through the activation of the non-neuronal α7 nAChR subtype, affecting the production of
cytokines. The
analgesic properties of α7 nAChR-selective compounds are mostly based on the activation of the cholinergic anti-inflammatory pathway. The molecular mechanism of
neuropathic pain relief mediated by the inhibition of α9-containing nAChRs is not fully understood yet, but the role of
immune factors in this process is becoming evident. To obtain appropriate drugs, a search of selective agonists, antagonists and modulators of α7- and α9-containing nAChRs is underway. The naturally occurring three-finger snake α-
neurotoxins and mammalian Ly6/uPAR
proteins, as well as neurotoxic
peptides α-
conotoxins, are not only sophisticated tools in research on nAChRs but are also considered as potential medicines. In particular, the inhibition of the α9-containing nAChRs by α-
conotoxins may be a pathway to alleviate
neuropathic pain. nAChRs are involved in the
inflammation processes during
AIDS and other
viral infections; thus they can also be means used in
drug design. In this review, we discuss the role of α7- and α9-containing nAChRs in the immune processes and in
pain.