Cholinergic

The N,N,N-trimethylethanolammonium cation, with an undefined counteranion, X⁻

Cholinergic agents are compounds which mimic the action of acetylcholine and/or butyrylcholine.^[1] In general, the word "choline" describes the various quaternary ammonium salts containing the N,N,N-trimethylethanolammonium cation. Found in most animal tissues, choline is a primary component of the neurotransmitter acetylcholine and functions with inositol as a basic constituent of lecithin. Choline also prevents fat deposits in the liver and facilitates the movement of fats into cells.

The parasympathetic nervous system, which uses acetylcholine almost exclusively to send its messages, is said to be almost entirely cholinergic. Neuromuscular junctions, preganglionic neurons of the sympathetic nervous system, the basal forebrain, and brain stem complexes are also cholinergic, as are the receptor for the merocrine sweat glands.

In neuroscience and related fields, the term cholinergic is used in these related contexts:

A substance (or ligand) is cholinergic if it is capable of producing, altering, or releasing acetylcholine, or butyrylcholine ("indirect-acting"), or mimicking their behaviours at one or more of the body's acetylcholine receptor ("direct-acting") or butyrylcholine receptor types ("direct-acting"). Such mimics are called parasympathomimetic drugs or cholinomimetic drugs.
A receptor is cholinergic if it uses acetylcholine as its neurotransmitter.^[2]
A synapse is cholinergic if it uses acetylcholine as its neurotransmitter.

^ Vardanyan, R.S.; Hruby, V.J. (2006). "Cholinomimetics". Synthesis of Essential Drugs. Elsevier. pp. 179–193. doi:10.1016/b978-044452166-8/50013-3. ISBN 978-0-444-52166-8. Cholinomimetics or cholinergic drugs are those drugs that cause effects similar to those resulting from introduction of acetylcholine, or simulation of ganglions of the parasympathetic nervous system. These drugs imitate action of endogenously released acetylcholine.
^ "Dorlands Medical Dictionary:cholinergic receptors".^{[permanent dead link]}

[Vardanyan_Hruby_2006_pp._179–193-1] Vardanyan, R.S.; Hruby, V.J. (2006). "Cholinomimetics". Synthesis of Essential Drugs. Elsevier. pp. 179–193. doi:10.1016/b978-044452166-8/50013-3. ISBN 978-0-444-52166-8. Cholinomimetics or cholinergic drugs are those drugs that cause effects similar to those resulting from introduction of acetylcholine, or simulation of ganglions of the parasympathetic nervous system. These drugs imitate action of endogenously released acetylcholine.

[urlDorlands_Medical_Dictionary:cholinergic_receptors-2] "Dorlands Medical Dictionary:cholinergic receptors".^{[permanent dead link]}

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