Sympathetic Fibers, Postganglionic

**Definition:** Nerve fibers which project from sympathetic ganglia to synapses on target organs. Sympathetic postganglionic fibers use norepinephrine as transmitter, except for those innervating eccrine sweat glands (and possibly some blood vessels) which use acetylcholine. They may also release peptide cotransmitters.

**Tree numbers:** - A08.675.542.075.800 - A08.675.542.100.800 - A08.800.050.050.050.800 - A08.800.800.060.050.800 - A11.671.501.075.800 - A11.671.501.100.800