peripheral (autonomic and somatic) nervous systems. In the autonomic (sympathetic and parasympathetic) nervous system, acetylcholine is released from all preganglionic neurons, as well as from postganglionic parasympathetic neurons. Degradation of acetylcholine by the enzyme acetylcholinesterase occurs in the synapse between the presynaptic and postsynaptic membranes. There are two types of pos...
