What is acetylcholine and what is it for?

What is acetylcholine?

Acetylcholine is a neurotransmitter that works at the level of theCentral Nervous System (CNS) and the Peripheral Nervous System (PNS)(1), whose main function is tomaintain synaptic communication between neuronsand even with other cells not properly related to the nervous system. (2)

This neurotransmitteris synthesized in neuronsand constitutes the main neurotransmitter of theCholinergic System(3) and for its synthesis 3 elements are required: acetyl COA, the enzyme choline acetylase and choline, regulated through acetylcholine receptors of the ionotropic and metabotropic type.

To highlight: This neurotransmittercan intervene in the contraction and relaxation of muscles, in the perception of pain, intervenes in the sleep-wake cycle(4), inlearningand consolidation of memories, among other functions.

On the other hand, acetylcholineis also synthesized in the pharmaceutical industry as a medicinein the form of a solution for clinical use, among which is for example in ophthalmology, to cause the contraction of the smooth muscle that surrounds the iris to produce miosis.

What is acetylcholine for?

Here we present the most relevant functions of this neurotransmitter in the CNS and PNS:

1. Allows muscle contraction and relaxation

As we have already mentioned, acetylcholine controls the emission of electrical impulses , which are nothing more than messages between the musculoskeletal system and the muscles.

These electrical impulses, signals, information or messages are what cause muscle excitement or relaxation and is what gives rise to locomotion.

Note: Acetylcholine, depending on the needs and the orders sent by the brain , can have both excitatory and inhibitory activity.

2. Control memory, memories and learning

Another of the functions of acetylcholine is that it intervenes in cognitive processes through the activation of cholinergic receptors located in areas of the brain such as the hippocampus, Amygdala and cerebral cortex.

You should know: This activation favors short- and long-term memory processes (5) , memory recovery, and the learning process.

3. Regulates the action of endocrine glands

The activation of the endocrine glands is also carried out through the activation of this neurotransmitter.

in the synthesis of (hormone that breast milk to be produced).

4. Reduces heart rate and blood pressure

Acetylcholine has an inhibitory function of cardiovascular activity on the neurotransmitters that stimulate the heart rate, since it would cause an overexcitation of cardiovascular activity.

This neurotransmitter with an inhibitory function, slows the heart rate and therefore reduces blood pressure, avoiding the problems caused by high blood pressure.

To highlight: Acetylcholine together with glutamate , Adrenaline , Norepinephrine and glycine are part of the main neurotransmitters of the CNS .

5. Promotes intestinal motility

Acetylcholine in the case of gastrointestinal activity, specifically at the level of the intestines, has an excitatory function, , Stimulating intestinal motility since, as we have commented, this substance acts on smooth and striated muscles.

Note: This favors the feeding process, from swallowing to the expulsion of feces .

6. Regulates sleep cycles

phase of the sleep-wake cycle. In this phase, it is the moment in which the

Likewise, acetylcholine is very important when stimulating neuronal connections when the wake phase is activated, that is, it activates the nervous system by sending it information.

You should know: happiness hormones such as dopamine and serotonin are also involved in the sleep-wake cycle.

7. Transmits nerve impulses from the senses to the brain

As described above, acetylcholine’s main function is to maintain communication between the different stimulus receptors such as touch, sight, smell, taste and hearing.

To highlight: All the stimuli captured by these sensory organs travel through the CNS in the form of electrical impulses to the brain, to be interpreted and create a response.

Key Conclusions

• Acetylcholine is a neurotransmitter that works at the level of the Central Nervous System and the Peripheral Nervous System. 
• This neurotransmitter has the function of maintaining synaptic communication between neurons and even with other cells.
• This neurotransmitter is synthesized in neurons with the intervention of acetyl COA, the enzyme cholineacetylase and choline.
• Acetylcholine can have both excitatory and inhibitory activity .