Postganglionic nerve fibers

Postganglionic fibers
Sympathetic connections of the ciliary and superior cervical ganglia.
Details
Identifiers
Latin	neurofibrae postganglionicae
Dorlands /Elsevier	n_06/12568789
TA	A14.2.00.010
FMA	76569
Anatomical terms of neuroanatomy [edit on Wikidata]

Acetylcholine

Norepinephrine

In the autonomic nervous system, fibers from the ganglion to the effector organ are called postganglionic fibers.

Neurotransmitters

The neurotransmitters of postganglionic fibers differ:

• In the parasympathetic division, neurons are cholinergic (that is, acetylcholine is the primary neurotransmitter).
• In the sympathetic division, neurons are mostly adrenergic (that is, epinephrine and norepinephrine function as the primary neurotransmitters). Two exceptions to this rule are the sympathetic innervation of sweat glands and arrectores pilorum muscles where the neurotransmitter at both pre and post ganglionic synapses is acetylcholine and the vessels in the renal cortex where dopamine is used as the main neurotransmitter. Another exception is the sympathetic innervation of the medulla of the adrenal glands, which is accomplished by preganglionic fibers, and subsequently uses acetylcholine as a neurotransmitter. The cells of the adrenal medulla are actually modified postganglionic neurons which secrete epinephrine and norepinephrine directly into the blood stream rather than into a synapse.^[1]
• In both divisions of the autonomic nervous system, postganglionic neurons express nicotinic acetylcholine receptors to receive signals from preganglionic neurons.^[2]

See also

• Preganglionic fibers
• Nerve fiber

References

1. Noback, Charles; David A. Ruggiero, Robert J. Demarest, Norman L. Strominger (2005). The Human Nervous System: Structure and Function (6th ed.). New Jersey: Humana Press. ISBN 978-1588290403.
2. Costanzo, Linda (2014). BRS Physiology (6th ed.). LWW. ISBN 9781451187953.

External links