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What Is Acetylcholine?



Acetylcholine was the first neurotransmitter to be discovered.

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Acetylcholine (often abbreviated ACh) is the most common neurotransmitter. It is located in both the central nervous system (CNS) and the peripheral nervous system (PNS).

Acetylcholine was the first neurotransmitter be be identified. It was discovered by Henry Hallett Dale in 1914 and its existence was later confirmed by Otto Loewi. Both individuals were awarded the Nobel Prize in Physiology/Medicine in 1936 for their discovery.

Acetylcholine acts as a neuromodulator in the CNS and PNS. Rather than engaging in direct synaptic transmission between specific neurons, neuromodulators act on a variety of neurons throughout the nervous system. In the central nervous system, acetylcholine acts as part of a neurotransmitter system and plays a role in attention and arousal. In the peripheral nervous system, this neurotransmitter is a major part of the autonomic nervous system and works to activate muscles.

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Siegal A & Sapru HN (2006) Essential Neuroscience. Revised 1st ed. Philadelphia: Lippincott, Williams & Wilkins.


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