What Is Acetylcholine and Why Is It Important?
Acetylcholine (ACh) is a chemical that plays an important role in many different body functions.
This article discusses how acetylcholine functions in the body as well as how it is produced.
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It also covers what can happen when acetylcholine function is impaired.
The name acetylcholine is derived from its structure.
It is a chemical compound made up of acetic acid and choline.
Acetylcholine Function
Acetylcholine has numerous functions in the body.
How Does Acetylcholine Affect Behavior?
Some cells of the body have what are known as cholinergic synapses.
Peripheral Nervous System
In the PNS, acetylcholine is a major part of thesomatic nervous system.
Within this system, it plays an excitatory role leading to the voluntary activation of muscles.
Within theautonomic system, acetylcholine controls a number of functions by acting on neurons in the sympatheticand parasympathetic systems.
For example, the brain might send out a signal to move the right arm.
The signal is carried by nerve fibers to the neuromuscular junctions.
The signal is transmitted across this junction by acetylcholine, triggering the desired response in those specific muscles.
Discovery
Acetylcholine was the first neurotransmitter to be identified.
It was discovered by Henry Hallett Dale in 1914, and its existence was later confirmed by Otto Loewi.
Both were awarded the Nobel Prize in Physiology or Medicine in 1936 for their discovery.
Choline and Acetylcholine
Acetylcholine production takes place in the nerve terminals of cholinergic neurons.
It is made by the choline acetyltransferase enzyme.
Choline is a nutrient precursor of acetylcholine.
The body uses choline to produce acetylcholine.
When people don’t consume enough choline, they may experience a range of negative health effects.
Because the body cannot produce enough choline on its own, it needs to be obtained from food.
Supplements containing choline are available.
Individuals who menstruate may need less because estrogen helps stimulate the synthesis of choline.
Symptoms include increased salivation, cramps, diarrhea, blurry vision, paralysis, and muscle twitches.
Alzheimer’s Disease
Alzheimer’s disease causes problems with memory and thinking.
It is an example of a condition that may be because of acetylcholine deficiency.
Myasthenia Gravis
Myasthenia gravis is a condition that leads to muscle weakness.
It can affect muscles in the arms, legs, neck, hands, and fingers.
It is an autoimmune condition that comes up whenever the body’s immune system attacks acetylcholine receptors.
Parkinson’s Disease
Parkinson’s disease is a degenerative neurological condition that causes tremors and involuntary movements.
For example, the venom of a black widow spider interacts with acetylcholine.
Medications That Affect Acetylcholine
Medications that affect acetylcholine are used to treat certain health conditions.
Such medications may include AChE inhibitors and anticholinergics.
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