Drugs and acetylcholine
Acetylcholine is the transmitter not only of parasympathetic terminations but also of ganglionic and neuromuscular transmission as well as of many synapses of the central nervous system.
The term cholinomimetic agents indicates the drugs which, by direct or indirectly acting mechanisms, reproduce the effects of acetylcholine.
The term cholinergic antagonists indicates the drugs which reduce the effects of acetylcholine, mainly by inhibiting its receptors.
Acetylcholine is a flexible molecule, i.e. likely to adopt a certain number of privileged conformations and to stimulate several types of receptors.