Acetylcholine

Acetylcholine (often abbreviated ACh) is an organic, polyatomic cation that acts as a neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS) in many organisms including humans. Acetylcholine is one of many neurotransmitters in the autonomic nervous system (ANS) and is the only neurotransmitter used in the motor division of the somatic nervous system (sensory neurons use glutamate and various peptides at their synapses). Acetylcholine is also the principal neurotransmitter in all autonomic ganglia.