Acetylcholine

cholinergicAChacetylcholine (ACh)acetyl choline acetylcholine (ACh)acetylcholine chlorideacetylcholine modulatorsacetylcholine neurotransmittersAcetylcholine/AChcholinomimetic
Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals, and humans, as a neurotransmitter—a chemical message released by nerve cells to send signals to other cells, such as neurons, muscle cells, and gland cells.wikipedia
703 Related Articles

Neurotransmitter

neurotransmittersexcitatory neurotransmitterneurotransmitter system
Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals, and humans, as a neurotransmitter—a chemical message released by nerve cells to send signals to other cells, such as neurons, muscle cells, and gland cells. In the brain, acetylcholine functions as a neurotransmitter and as a neuromodulator.
Furthermore, Otto Loewi is credited with discovering acetylcholine (ACh)—the first known neurotransmitter.

Anticholinergic

anticholinergicsanticholinergic druganticholinergic syndrome
Substances that interfere with acetylcholine activity are called anticholinergics.
An anticholinergic agent is a substance that blocks the action of the neurotransmitter acetylcholine at synapses in the central and the peripheral nervous system.

Cholinergic

cholinergic systemCholinergic agonistCholinergic neurons
Parts in the body that use or are affected by acetylcholine are referred to as cholinergic.
Cholinergic agents are compounds which mimic the action of acetylcholine and/or butyrylcholine.

Choline

choline salicylateanticholinergicCholine bitartrate
Its name is derived from its chemical structure: it is an ester of acetic acid and choline. The enzyme acetylcholinesterase converts acetylcholine into the inactive metabolites choline and acetate. Acetylcholine is synthesized in certain neurons by the enzyme choline acetyltransferase from the compounds choline and acetyl-CoA.
Choline is required to produce acetylcholine – a neurotransmitter – and S-adenosyl methionine, a universal methyl donor involved in the synthesis of homocysteine.

Nerve agent

nerve gasnerve agentsnerve gases
Numerous venoms and toxins produced by plants, animals, and bacteria, as well as chemical nerve agents such as Sarin, cause harm by inactivating or hyperactivating muscles via their influences on the neuromuscular junction.
The disruption is caused by the blocking of acetylcholinesterase, an enzyme that catalyzes the breakdown of acetylcholine, a neurotransmitter.

Neuromodulation

neuromodulatorneuromodulatorsvolume transmission
In the brain, acetylcholine functions as a neurotransmitter and as a neuromodulator.
Major neuromodulators in the central nervous system include: dopamine, serotonin, acetylcholine, histamine, norepinephrine and several neuropeptides.

Neuromuscular junction

neuromuscularneuromuscular junctionsneuromuscular transmission
Acetylcholine is the neurotransmitter used at the neuromuscular junction—in other words, it is the chemical that motor neurons of the nervous system release in order to activate muscles. Certain neurotoxins work by inhibiting acetylcholinesterase, thus leading to excess acetylcholine at the neuromuscular junction, causing paralysis of the muscles needed for breathing and stopping the beating of the heart.
In vertebrates, motor neurons release acetylcholine (ACh), a small molecule neurotransmitter, which diffuses across the synaptic cleft and binds to nicotinic acetylcholine receptors (nAChRs) on the cell membrane of the muscle fiber, also known as the sarcolemma.

Sarin

sarin gasGBnerve gas
Numerous venoms and toxins produced by plants, animals, and bacteria, as well as chemical nerve agents such as Sarin, cause harm by inactivating or hyperactivating muscles via their influences on the neuromuscular junction.
Like some other nerve agents that affect the neurotransmitter acetylcholine, sarin attacks the nervous system by interfering with the degradation of the neurotransmitter acetylcholine at neuromuscular junctions.

Muscarinic acetylcholine receptor

muscarinicmuscarinic receptormuscarinic receptors
Drugs that act on muscarinic acetylcholine receptors, such as atropine, can be poisonous in large quantities, but in smaller doses they are commonly used to treat certain heart conditions and eye problems.
They play several roles, including acting as the main end-receptor stimulated by acetylcholine released from postganglionic fibers in the parasympathetic nervous system.

Nicotinic acetylcholine receptor

nicotinic acetylcholine receptorsnicotinicnicotinic receptors
The addictive qualities of nicotine are derived from its effects on nicotinic acetylcholine receptors in the brain. Nicotinic acetylcholine receptors are ligand-gated ion channels permeable to sodium, potassium, and calcium ions.
Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine.

Sympathetic nervous system

sympatheticsympathetic nervesympathetic nerves
Acetylcholine is also a neurotransmitter in the autonomic nervous system, both as an internal transmitter for the sympathetic nervous system and as the final product released by the parasympathetic nervous system.
At the synapses within the ganglia, preganglionic neurons release acetylcholine, a neurotransmitter that activates nicotinic acetylcholine receptors on postganglionic neurons.

Acetylcholinesterase

acetylcholine esteraseAChEacetycholinesterase
The enzyme acetylcholinesterase converts acetylcholine into the inactive metabolites choline and acetate.
It is an enzyme that catalyzes the breakdown of acetylcholine and of some other choline esters that function as neurotransmitters.

Choline acetyltransferase

CHATcholine O-acetyltransferase
Acetylcholine is synthesized in certain neurons by the enzyme choline acetyltransferase from the compounds choline and acetyl-CoA.
Choline acetyltransferase (commonly abbreviated as ChAT, but sometimes CAT) is a transferase enzyme responsible for the synthesis of the neurotransmitter acetylcholine.

Atropine

atropine sulfateatropine eye dropsAtropine methonitrate
Drugs that act on muscarinic acetylcholine receptors, such as atropine, can be poisonous in large quantities, but in smaller doses they are commonly used to treat certain heart conditions and eye problems.
However, by blocking the action of acetylcholine at muscarinic receptors, atropine also serves as a treatment for poisoning by organophosphate insecticides and nerve agents, such as tabun (GA), sarin (GB), soman (GD), and VX.

Receptor (biochemistry)

receptorreceptorscellular receptors
Like many other biologically active substances, acetylcholine exerts its effects by binding to and activating receptors located on the surface of cells.
For example, an acetylcholine receptor recognizes and responds to its endogenous ligand, acetylcholine.

Ligand-gated ion channel

ionotropicionotropic receptorligand-gated ion channels
Nicotinic acetylcholine receptors are ligand-gated ion channels permeable to sodium, potassium, and calcium ions.
It consists of a pentamer of protein subunits (typically ααβγδ), with two binding sites for acetylcholine (one at the interface of each alpha subunit).

Basal forebrain

Forebrain cholinergic nuclei
In the CNS, cholinergic projections from the basal forebrain to the cerebral cortex and hippocampus support the cognitive functions of those target areas.
These structures are important in the production of acetylcholine, which is then distributed widely throughout the brain.

Neuron

neuronsnerve cellsnerve cell
Acetylcholine is synthesized in certain neurons by the enzyme choline acetyltransferase from the compounds choline and acetyl-CoA.
Some other types of neurons have consistent effects, for example, "excitatory" motor neurons in the spinal cord that release acetylcholine, and "inhibitory" spinal neurons that release glycine.

Motor neuron

motor neuronsmotormotor development
Acetylcholine is the neurotransmitter used at the neuromuscular junction—in other words, it is the chemical that motor neurons of the nervous system release in order to activate muscles.
All vertebrate motor neurons are cholinergic, that is, they release the neurotransmitter acetylcholine.

Muscarine

muscarinic
They are named for chemicals that can selectively activate each type of receptor without activating the other: muscarine is a compound found in the mushroom Amanita muscaria; nicotine is found in tobacco.
These new findings set into motion research on the pharmacology of muscarine and muscarine-like substances that are structurally related to acetylcholine.

Hexamethonium

benzohexoniumhexamethonium bromidehexamethonium compounds
The muscle-type can be selectively blocked by curare, the neuronal-type by hexamethonium.
Hexamethonium is a non-depolarising ganglionic blocker, a nicotinic (nAChR) receptor antagonist that acts in autonomic ganglia by binding mostly in or on the nAChR receptor, and not the acetylcholine binding site itself.

Neurotoxin

neurotoxicneurotoxinsneurotoxicity
Certain neurotoxins work by inhibiting acetylcholinesterase, thus leading to excess acetylcholine at the neuromuscular junction, causing paralysis of the muscles needed for breathing and stopping the beating of the heart.
BTX functions peripherally to inhibit acetylcholine (ACh) release at the neuromuscular junction through degradation of the SNARE proteins required for ACh vesicle-membrane fusion.

Rapid eye movement sleep

REM sleepREMrapid eye movement
ACh has also been shown to promote REM sleep.
Electrical and chemical activity regulating this phase seems to originate in the brain stem and is characterized most notably by an abundance of the neurotransmitter acetylcholine, combined with a nearly complete absence of monoamine neurotransmitters histamine, serotonin, and norepinephrine.

Curare

Curare poisoningcurariformcurarizing
The muscle-type can be selectively blocked by curare, the neuronal-type by hexamethonium.
In 1914, Henry Hallett Dale (1875–1968) described the physiological actions of acetylcholine.

Inositol trisphosphate

inositol triphosphateIP3inositol 1,4,5-trisphosphate
The M1, M3, and M5 subtypes are G q -coupled; they increase intracellular levels of IP 3 and calcium by activating phospholipase C.
The discovery that a hormone can influence phosphoinositide metabolism was made by Mabel R. Hokin (1924–2003) and her then husband Lowell E. Hokin in 1953, when they discovered that radioactive 32 P phosphate was incorporated into the phosphatidylinositol of pancreas slices when stimulated with acetylcholine.