Alpha 7 nicotinic acetylcholine receptors: Molecular pharmacology and role in neuroprotection

There is a growing body of evidence suggesting that the neuronal nicotinic receptor (nAChR) family is a valid target for a range of neuropathologies particularly relating to neuroprotection. The two main subtypes of nAChR, the α7 and α4β2, are homo-oligomeric and hetero-oligomeric complexes, which display low and high affinity for nicotine, respectively. The α7 receptor has been implicated in diverse functions, such as stabilizing synapse formation during development, learning and memory, and neuronal survival. It is purported that α7 might play a role in a range of diseases including epilepsy, schizophrenia, Alzheimer's disease and anxiety disorders. Ric-3 has been recently shown to modulate nAChR subtype trafficking to the cell surface, although excess levels of this protein may have converse effects. This suggests a novel strategy for therapeutically manipulating the nAChRs, via a novel trafficking molecule.