Editing Neurotransmitter (section)

{{short description|Chemical substance that enables neurotransmission}}
{{For|an introduction to concepts and terminology used in this article|Chemical synapse}}
{{Use dmy dates|date=June 2018}}
{{Synapse map}}

A '''neurotransmitter''' is a [[signaling molecule]] secreted by a [[neuron]] to affect another cell across a [[Chemical synapse|synapse]]. The cell receiving the signal, or target cell, may be another neuron, but could also be a [[gland]] or [[muscle cell]].<ref>{{Cite book |last1=Smelser |first1=Neil J. |title=International encyclopedia of the social & behavioral sciences |last2=Baltes |first2=Paul B. |date=2001 |publisher=Elsevier |isbn=978-0-08-043076-8 |edition=1st |location=Amsterdam New York}}</ref>

Neurotransmitters are released from [[synaptic vesicles]] into the [[synaptic cleft]] where they are able to interact with [[neurotransmitter receptor]]s on the target cell. Some neurotransmitters are also stored in [[large dense core vesicles]].<ref>{{Cite journal |last=Edwards |first=Robert H |date=December 1998 |title=Neurotransmitter release: Variations on a theme |url=https://linkinghub.elsevier.com/retrieve/pii/S0960982207005519 |journal=Current Biology |volume=8 |issue=24 |pages=R883–R885 |doi=10.1016/s0960-9822(07)00551-9 |pmid=9843673 |bibcode=1998CBio....8.R883E |issn=0960-9822}}</ref> The neurotransmitter's effect on the target cell is determined by the receptor it binds to. Many neurotransmitters are synthesized from simple and plentiful precursors such as [[amino acid]]s, which are readily available and often require a small number of [[biosynthetic]] steps for conversion.{{cn|date=March 2025}}

Neurotransmitters are essential to the function of complex neural systems. The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified.<ref>{{cite book | vauthors = Cuevas J | chapter = Neurotransmitters and Their Life Cycle |date=2019-01-01 | title =Reference Module in Biomedical Sciences |publisher=Elsevier |doi=10.1016/b978-0-12-801238-3.11318-2 |isbn=978-0-12-801238-3 }}</ref> Common neurotransmitters include [[Glutamate (neurotransmitter)|glutamate]], [[GABA]], [[acetylcholine]], [[glycine]], [[dopamine]] and [[norepinephrine]].