The neuronal acetylcholine receptor subunit alpha-5, or alpha-5 nicotinic acetylcholine receptor (α5 nAChR) also known as the α5 receptor is a type of ligand gated neuronal type subunit of the nicotinic acetylcholine receptor involved in pain regulation encoded in the human by the CHRNA5 gene. This receptor is commonly associated with nicotine addiction, immunotherapy, cancer, pain and attention.