Molecular weight: 146
Formula: C7H16NO2.
Acetylcholine is a molecule which is essentially a neurotransmitter. It is the main mediator of the parasympathetic nervous system. There are 2 main types of receptors, nicotinic and muscarinic. The nicotinic receptors are present mainly at the neuromuscular junctions of skeletal muscle and the central nervous system (CNS). The muscarinic receptors are of 5 types (M1-5) and they are found in the CNS and in the respiratory, gastrointestinal, and circulatory system.