Table of ContentsView AllTable of ContentsWhat it IsAcetylcholine’s FunctionImbalance and DeficiencyMedicationsFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
What it Is
Acetylcholine’s Function
Imbalance and Deficiency
Medications
Frequently Asked Questions
Acetylcholine signals your muscles to contract. It also plays a role in cognition and can affect behaviors such as motivation and attention. An imbalance in acetylcholine can cause conditions that are related to these functions like Parkinson’s disease and Alzheimer’s disease.
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What Is Acetylcholine?
Acetylcholine is aneurotransmitterfound in the central nervous system (CNS) andperipheral nervous system(PNS). It plays an important role in many of your body’s functions, including muscle movement, memory and cognition, REM sleep, and attention and learning.
More than two decades later, Dale and Otto Loewi from Graz shared the Nobel Prize in Physiology or Medicine for their work on chemical neurotransmission.
Acetylcholine is released from cholinergic nervesynapsesand acts on presynaptic (transmitter) and postsynaptic (receiver) acetylcholine receptors.
Dilates Blood Vessels
Acetylcholine plays a role in regulating blood pressure. When blood flows, it creates friction that can be seen on image signaling technology focusing on the endothelium, the cell barrier between your blood and blood vessel wall.
One ex vivo (outside of a living body) animal study on rats' main arteries found that this friction triggers the release of acetylcholine, which triggers calcium release from your endothelial cells, nitric oxide production (a known vasodilator, which relaxes or dilates blood vessels), and artery relaxation.
Human clinical trials are still needed before science can fully explain how acetylcholine works to dilate blood cells in the human body.
Contracts Smooth Muscles
Smooth muscles are those lining the walls of organs and tubular structures, including the intestine, bladder, airway,uterus, blood vessels, and stomach. Acetylcholine in the neuromuscular junction (located between the motor nerve and skeletal muscle) acts on nerve fibers, sending messages from the brain to targeted muscles, signaling them to respond with movement.
Here’s how it works, according to studies conducted on mice:
Acetylcholine plays an important role in muscle actions, so any drugs that influence this neurotransmitter can cause movement disruption and even paralysis.
Causes Erections
Slows Heart Rate
Acetylcholine is the predominant neurotransmitter in the parasympathetic nervous system. When your heart rate increases beyond what’s normal, acetylcholine is released to slow your heart rate and contractions until it goes back to baseline.
Stimulates Secretions
Examples include:
Acetylcholine sends messages along nerve cells through the nervous systems. All of your body’s movements depend on this communication. This means any disruption to acetylcholine functioning compromises this process and can result in illness.
Acetylcholine in the brain also plays crucial roles in memory and cognitive functioning. As such, it is associated with higher brain functions and some neurodegenerative brain diseases.
Alzheimer’s Disease
People with Alzheimer’s disease have low levels of acetylcholine. It may be because the plaques that form in the brains of people with Alzheimer’s disease increase the activity of chemicals that break down acetylcholine.
Parkinson’s Disease
Parkinson’s disease affects the muscles and causes involuntary movements and tremors. Research suggests that an imbalance of acetylcholine may play a role in the development of this condition.
Myasthenia Gravis
Myasthenia gravis is an autoimmune condition where the body’s immune system mistakenly attacks acetylcholine receptors. People with this condition experience weakening of the muscles in the arms, hands, fingers, legs, and neck.
Toxins and Venom
Organophosphates are insecticides that interfere with the enzyme that breaks down acetylcholine. Long-term exposure to these chemicals can cause an increase in acetylcholine and problems such as anxiety, memory loss, headache, and nausea and vomiting.
The venom of the black widow spider also affects acetylcholine. After a black widow bite, acetylcholine levels in the body increase, which can cause symptoms like severe muscle contractions, muscle spasms, and paralysis.
Medications That Affect Acetylcholine
Acetylcholine receptors can be targeted and manipulated with medications to adjust how your body functions in a disease state.
Cholinergic nerve receptors are those that receive and bind with acetylcholine. They can be found all over the body, including in muscle tissue. If there is any issue with these receptors or the appropriate release and uptake of acetylcholine,abnormal muscle functionmay result. In such cases, anticholinergic drugs may be necessary.
Summary
Acetylcholine is a neurotransmitter that has a wide range of functions in the body, from muscle movement to memory and cognition. An imbalance of this neurotransmitter can lead to a number of health conditions, including Alzheimer’s disease and Parkinson’s disease. Certain toxins and venoms can also interfere with acetylcholine, causing severe health problems.
Medications that affect acetylcholine are used to treat conditions ranging from asthma and urinary incontinence to Parkinson’s disease symptoms.
A Word From Verywell
Researchers are only just beginning to understand acetylcholine’s role in diseases like Alzheimer’s and Parkinson’s. There is no cure for these conditions, but medications that affect the balance of this important neurotransmitter can help ease symptoms. Talk to your healthcare provider about whether or not these treatments are right for you.
Frequently Asked QuestionsAcetylcholine is critical in the healthy functioning of your heart. It helps to regulate your heartbeat, blood pressure, and heart muscle contractions.Acetylcholinesterase is a cholinergic enzyme that breaks down acetylcholine into acetic acid and choline. This enzyme is found at postsynaptic neuromuscular junctions, especially in muscles and nerves.Too much acetylcholine in the joints and synapses can cause symptoms like cramps, muscle weakness, paralysis, blurry vision, and gastrointestinal problems like diarrhea.You can lower levels of acetylcholine with prescription anticholinergic drugs, but the appropriate drug depends on the body system. For example, acetylcholine imbalance associated with brain conditions may be treated differently than that of asthmatic conditions. Your doctor can help determine what, if any, medication is necessary.
Acetylcholine is critical in the healthy functioning of your heart. It helps to regulate your heartbeat, blood pressure, and heart muscle contractions.
Acetylcholinesterase is a cholinergic enzyme that breaks down acetylcholine into acetic acid and choline. This enzyme is found at postsynaptic neuromuscular junctions, especially in muscles and nerves.
Too much acetylcholine in the joints and synapses can cause symptoms like cramps, muscle weakness, paralysis, blurry vision, and gastrointestinal problems like diarrhea.
You can lower levels of acetylcholine with prescription anticholinergic drugs, but the appropriate drug depends on the body system. For example, acetylcholine imbalance associated with brain conditions may be treated differently than that of asthmatic conditions. Your doctor can help determine what, if any, medication is necessary.
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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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