acetylcholine

American  

[uh-seet-l-koh-leen, uh-set-] / əˌsit lˈkoʊ lin, əˌsɛt- /

noun

1. Biochemistry. the acetic acid ester of choline, C 7 H 17 NO 3 , released and hydrolyzed during nerve conduction and causing muscle action by transmitting nerve impulses across synapses.

2. Pharmacology. this substance used in its chloride form in eye surgery. ACh

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acetylcholine British  

/ -lɪn, ˌæsɪtaɪlˈkəʊliːn /

noun

1. a chemical substance secreted at the ends of many nerve fibres, esp in the autonomic nervous system, and responsible for the transmission of nervous impulses. Formula: CH 3 CO 2 (CH 2 ) 2 N (CH 3 ) 3 ⁺

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acetylcholine Scientific  

/ ə-sēt′l-kō′lēn′ /

1. A substance that is released at the junction between neurons and skeletal muscle fibers, at the nerve endings of the parasympathetic nervous system, and across synapses in the central nervous system, where it acts as a neurotransmitter. Chemical formula: C ₇ H ₁₆ NO ₂ .

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Other Word Forms

• acetylcholinic
  adjective

Etymology

Origin of acetylcholine

First recorded in 1905–10; acetyl + choline

Example Sentences

See Examples For:

acetylcholine

"The greater the increase in acetylcholine the more likely the mice were to change their future choices. Our results demonstrated the importance of acetylcholine in breaking habits and enabling new choices to be made."

From Science Daily ● Jun. 8, 2026

Caffeine blocks adenosine, a chemical that slows the activity of important brain messengers such as dopamine and acetylcholine.

From Science Daily ● May 13, 2026

"They're using acetylcholine to communicate, but without any of the usual cellular machinery that neurons rely on to release it."

From Science Daily ● Mar. 28, 2026

This revealed that tuft cells were releasing acetylcholine, a signaling molecule typically associated with nerve cells.

From Science Daily ● Mar. 28, 2026

By this means a precise balance is struck and the body never builds up a dangerous amount of acetylcholine.

From "Silent Spring" by Rachel Carson