Types of neurotransmitters: functions and classification

What are neurotransmitters and what function do they perform in our brain?

The neurotransmitters are chemicals created by the body that transmit signals (i.e. information) from one neuron to the next through contact points called synapses.

When this occurs, the chemical is released by vesicles in the pre-synaptic neuron, crosses the synaptic space and acts by changing the action potential in the post-synaptic neuron.

There are different types of neurotransmitters, each with different functions.. In fact, the study of this class of substances is fundamental to understand how the human mind works. In addition, there are different classification systems, intermediate concepts that allow us to see the affinities and differences between these substances: indolamines, catecholamines, etc.

In this article we will review some of the different types of neurotransmitters, the most significant ones, taking into account the relationships they establish between them in the functioning of the nervous system.

Main neurotransmitters and their functions

The list of known neurotransmitters has been increasing since the 1980s, and at the present time more than 60 neurotransmitters have been counted..

This is not surprising, considering the complexity and versatility of the human brain. All kinds of mental processes take place in it, from managing emotions to planning and strategizing, from performing involuntary movements to using language.

All this variety of tasks behind many neurons coordinating with each other. to make the different parts of the brain function in a coordinated manner, and for this it is necessary that they have a mode of communication capable of adapting to many situations.

The use of different types of neurotransmitters makes it possible to regulate in many different ways the way in which different groups of nerve cells are activated. For example, a certain occasion may require that serotonin levels go down and dopamine levels go up, and that will have a certain consequence on what happens in our mind. Thus, the existence of the great variety of neurotransmitters allows the nervous system to have a wide range of behaviors, which is necessary to adapt to a constantly changing environment.

In short, having more neurotransmitters involved in the functioning of the nervous system (and their corresponding receptors on nerve cells) means that there is more variety of possible interactions between groups of neurons. But, what are the most important types of neurotransmitters in the human body and what functions do they perform? The main neurochemicals are listed below.

1. Serotonin

This neurotransmitter is synthesized from tryptophan, an amino acid that is not manufactured by the body, so it must be supplied through the diet. Serotonin (5-HT) is commonly referred to as the happiness hormonebecause low levels of this substance are associated with depression and obsession. It belongs to the group of indolamines.

In addition to its relationship with mood, 5-HT has several functions within the body, including: its fundamental role in digestion, control of body temperature, its influence on sexual desire and its role in regulating the sleep-wake cycle.

Excess serotonin can cause a range of symptoms of varying severity, but in the right measure, it is believed to help combat stress and anxiety. In addition, there are natural ways to boost the power of serotonin on our central nervous system, such as moderate exercise.

• If you want to know more, you can visit our article: "Serotonergic syndrome: causes, symptoms and treatment".

2. Dopamine

Dopamine is another of the best known neurotransmitters, because it is involved in addictive behaviors. it is involved in addictive behaviors and is the cause of pleasurable sensations.. However, its functions also include the coordination of certain muscle movements, memory regulation, cognitive processes associated with learning and decision-making.

• To know more: "Dopamine: 7 essential functions of this neurotransmitter".

3. Endorphins

Have you noticed that after going for a run or doing physical exercise you feel better, more lively and energetic? Well, this is mainly due to endorphins, a natural drug that is released by our body and produces a feeling of pleasure and euphoria.

Some of its functions are: they promote calmness, improve mood, reduce pain, delay the aging process, or delay the aging process.They delay the aging process or enhance the functions of the immune system.

4. Adrenaline (epinephrine)

Adrenaline is a neurotransmitter that triggers survival mechanisms.It is associated with situations in which we have to be alert and activated because it allows us to react in stressful situations.

In short, adrenaline fulfills both physiological functions (such as the regulation of Blood Pressure or respiratory rate and pupil dilation) and psychological (keeping us alert and more sensitive to any stimulus).

• To learn more about this chemical substance, you can read our post: "Adrenaline, the hormone that activates us".

5. Noradrenaline (norepinephrine)

Adrenaline is involved in different brain functions and is related to motivation, anger or sexual pleasure. Noradrenaline imbalance is associated with depression and anxiety.

6. Glutamate

Glutamate is the most important excitatory neurotransmitter of the central nervous system.. It is especially important for memory and its retrieval, and is considered as the main mediator of sensory, motor, cognitive, emotional information. In a way, it stimulates several mental processes of essential importance.

Research affirms that this neurotransmitter is present in 80-90% of brain synapses. Excess glutamate is toxic to neurons and is related to diseases such as epilepsy, stroke or amyotrophic lateral disease.

7. GABA

GABA (gamma-aminobutyric acid) acts as an inhibitory messenger, thus slowing down the action of excitatory neurotransmitters.. It is widely distributed in the neurons of the cortex, and contributes to motor control, vision, regulates anxiety, among other cortical functions.

On the other hand, this is one of the types of neurotransmitters that does not cross the blood-brain barrier, so it must be synthesized in the brain. Specifically, it is generated from glutamate.

• Learn more about this neurotransmitter by clicking here.

8. Acetylcholine

As a curiosity, this is the first neurotransmitter to be discovered.... This occurred in 1921 and the discovery was made by Otto Loewi, a German biologist who won the Nobel Prize in 1936. Acetylcholine is widely distributed throughout the synapses of the central nervous system, but it is also found in the peripheral nervous system.

Some of the most prominent functions of this neurochemical are: it is involved in muscle stimulation, in the transition from sleep to wakefulness, and in memory and association processes..

Classification of neurotransmitters

The types of neurotransmitters can be classified on the basis of these categories, each of which encompasses several substances:

1. Amines

These are neurotransmitters that derived from various amino acids, such as tryptophan such as, for example, tryptophan. In this group are: Norepinephrine, epinephrine, dopamine or serotonin.

2. Amino acids

Unlike the previous ones (which are derived from different amino acids), these are amino acids. For example: Glutamate, GABA, aspartate or glycine.

3. Purines

Recent research indicates that purines such as ATP or adenosine also act as chemical messengers. also act as chemical messengers.

4. Gases

Nitric oxide is the main neurotransmitter in this group.

5. Peptides

Peptides are widely distributed throughout the brain. For example: endorphins, dynorphins and tachykinins..

6. Esters

This group includes acetylcholine.

Its function

We must not forget that, although each of the types of neurotransmitters can be associated with certain functions in the nervous system (and, therefore, with certain effects at the psychological level), they are not elements with intentions and an objective to follow, so that their repercussions on us are purely circumstantial and depend on the context.

In other words, neurotransmitters have the effects they have because our organism has evolved to make this exchange of substances something that helps us to survive, by enabling the coordination of different cells and organs in the body..

Therefore, when we take drugs that emulate the functioning of these neurotransmitters, they often have side effects that can even be the opposite of the expected effect, if they interact abnormally with the substances already in our nervous system. The balance that is maintained in the functioning of our brain is somewhat fragile, and the neurotransmitters do not learn to adapt their influence on us to fulfill what is supposed to be "their function"; that is what we should be concerned about.

In addition, there are certain addictive substances that are capable of altering the medium and long-term functioning of nerve cells by substituting some neurotransmitters at key points. Therefore, in order to treat addicted people, it is essential to intervene in behavior and also in brain functioning.

On the other hand, to reduce the behavior of a human being to the existence of types of neurotransmitters is to fall into the error of excessive reductionism, given that behavior does not arise spontaneously from the brainbut arises from the interaction between the living being and the environment.

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