acetylcholine

acetylcholine
The acetic ester of choline, the neurotransmitter substance at cholinergic synapses, which causes cardiac inhibition, vasodilation, gastrointestinal peristalsis, and other parasympathetic effects. It is liberated from preganglionic and postganglionic endings of parasympathetic fibers and from preganglionic fibers of the sympathetic as a result of nerve injuries, whereupon it acts as a transmitter on the effector organ; it is hydrolyzed rapidly into choline and acetic acid by acetylcholinesterase in the tissues and by pseudocholinesterase in the blood.
- a. chloride a miotic, administered as an ophthalmic solution for parasympathomimetic effect; used in cataract surgery.

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ace·tyl·cho·line ə-.set-əl-'kō-.lēn, -.sēt-; .as-ə-.tēl- n a neurotransmitter C7H17NO3 released at autonomic synapses and neuromuscular junctions, active in the transmission of nerve impulses, and formed enzymatically in the tissues from choline
ace·tyl·cho·lin·ic -kō-'lin-ik adj

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n.
the acetic acid ester of the organic base choline: the neurotransmitter released at the synapses of parasympathetic nerves and at neuromuscular junction. After relaying a nerve impulse, acetylcholine is rapidly broken down by the enzyme cholinesterase. anticholinergic drugs block the action of acetylcholine at receptor sites; anticholinesterase and acetylcholinesterase inhibitor prolong the activity of acetylcholine by blocking cholinesterase.

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ac·e·tyl·cho·line (ACh) (as″ə-təl-) (as″ə-tēl-koґlēn) a reversible acetic acid ester of choline; it is a cholinergic agonist and serves as a neurotransmitter at the myoneural junctions of striated muscles, at autonomic effector cells innervated by parasympathetic nerves, at the preganglionic synapses of the sympathetic and parasympathetic nervous systems, and at various sites in the central nervous system. ACh has few therapeutic applications owing to its diffuse action and rapid hydrolysis by acetylcholinesterase (AChE); synthetic derivatives are used for more specific, prolonged action. ACh is used as a vasodilator in pharmacoangiography, administered by intraarterial infusion.

Medical dictionary. 2011.

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Look at other dictionaries:

  • Acetylcholine — IUPAC name …   Wikipedia

  • Acetylcholine — Acétylcholine Pour les articles homonymes, voir Ach. Acétylcholine …   Wikipédia en Français

  • ACÉTYLCHOLINE — L’acétylcholine (ACh) est l’ester acétique de la choline, corps basique azoté dérivé de l’ammonium quaternaire. Formule de l’acétylcholine: 廓 acétoxyéthyl triméthyl ammonium. L’ACh a été préparée par voie synthétique en 1867 et peut être obtenue… …   Encyclopédie Universelle

  • acetylcholine — n. 1. a neurotransmitter released by the transmitting dendron at autononmous synapses and at neuromuscular junctions. It is a quaternary amine with an obligatory negative counterion. The nominal formula for the hydroxide form is {C7H17NO3}.… …   The Collaborative International Dictionary of English

  • acetylcholine — acetylcholine. См. ацетилхолин. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • acetylcholine — [as΄i til΄kō′lēn] n. [ ACETYL + CHOLINE] the acetic acid ester of choline, (CH3) 3N(OH)CH2CH2OCOCH3, found in many body tissues, esp. at neuromuscular junctions, acting as a nerve impulse transmitter: its chloride or bromide is used in medicine… …   English World dictionary

  • Acétylcholine — Pour les articles homonymes, voir ACh. Acétylcholine …   Wikipédia en Français

  • acetylcholine — n. the acetic acid ester of the organic base choline: the neurotransmitter released at the synapses of parasympathetic nerves and at neuromuscular junctions. After relaying a nerve impulse, acetylcholine is rapidly broken down by the enzyme… …   The new mediacal dictionary

  • acetylcholine — Acetyl ester of choline. Perhaps the best characterized neurotransmitter, particularly at neuromuscular junctions. ACh can be either excitatory or inhibitory, and its receptors are classified as nicotinic or muscarinic, according to their… …   Dictionary of molecular biology

  • acetylcholine — acetilcholinas statusas T sritis chemija formulė Formulę žr. priede. priedas( ai) Grafinis formatas atitikmenys: angl. acetylcholine rus. ацетилхолин ryšiai: sinonimas – 2 etanoiloksietiltrimetilamonis …   Chemijos terminų aiškinamasis žodynas

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