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

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

From Science Daily • Mar. 28, 2026

In contrast, mice that lacked the ability to produce acetylcholine in their tuft cells continued eating normally.

From Science Daily • Mar. 28, 2026

Those receptors usually respond to acetylcholine, a neurotransmitter involved in everything from muscle activation to attention.

From Slate • Jun. 11, 2025

What we know now is that nicotine is a chemical compound that acts on receptors in the brain called nicotinic acetylcholine receptors, or nAChRs.

From Slate • Jun. 11, 2025

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