parasympathetic nerve


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par·a·sym·pa·thet·ic nerve

one of the nerves of the parasympathetic nervous system.

par·a·sym·pa·thet·ic nerve

(par'ă-sim'pă-thet'ik nĕrv)
One of the nerves of the parasympathetic nervous system.

parasympathetic nerve

A nerve composed of axons of the parasympathetic division of the autonomic nervous system. Parasympathetic innervation is always a chain of two consecutive axons. The first axon, the preganglionic parasympathetic axon, has its cell body in the brainstem or in the intermediate gray column of spinal cord segments S2–S4; the first axon leaves the brainstem through the oculomotor (CN III), facial (CN VII), glossopharyngeal (CN IX), or vagus (CN X) nerve, or it leaves the sacral spinal cord through a pelvic splanchnic nerve. The second axon in the chain, the postganglionic parasympathetic axon, has its cell body in a peripheral ganglion near its target tissue. The main transmitter used by both pre- and postganglionic parasympathetic axons is acetylcholine. In general, stimulation of parasympathetic nerves relaxes the body tone.
See also: nerve
References in periodicals archive ?
Specifically, nitrous oxide (NO) is released alongside ACh from parasympathetic nerves but opposes the actions of ACh, limiting bronchoconstriction in normal circumstances.
Scorpion venom stimulates both sympathetic and parasympathetic nerves.
These include the iris; ciliary body; parasympathetic nerves to the eye socket that cause the pupil to become small and cause the lens to focus for near work; and cranial nerves, which control oculormotor movements such as tracking, convergence, or divergence.
The autonomic nervous system, or ANS, is composed of two opposing divisions-the sympathetic and parasympathetic nerves, which check one another and thus control critical body functions outside of conscious awareness.
Latent Chagas' does injure the stomach and parasympathetic nerves in the digestive system.
The infection can also affect nerves within the vulva, which then affects the parasympathetic nerves in the bladder.

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