In our body there are biologically active substances involved in the transmission of electrochemical impulse from one nerve cell to another, as well as from nerve cells to other cells, for example – to muscle or glandular. These substances are called ” neurotransmitters “(neurotransmitters) or” neurotransmitters ” (neurotransmitters).
Officially, neurotransmitters are not considered hormones, because they are released not into the blood, but into the synaptic gap – a narrow space (gap) between two nerve cells (or into the gap between the nerve and muscle cells). But in General, neurotransmitters behave like hormones, if we understand by hormones signaling chemicals produced by some cells of the body and affecting other cells. Simply put, neurotransmitters, like hormones, are mediating substances by which some cells influence others. In addition, the same substances in our body can act as neurotransmitters, and as hormones. An example is dopamine, which we have already talked about. Or here’s another example-neurotransmitter serotonin as a hormone performs the following functions:
- increases blood clotting, contributing to the aggregation (adhesion) of blood platelets and the formation of blood clots; the release of serotonin from damaged tissues is one of the factors that ensure blood clotting at the site of damage;
- increases the permeability of capillaries and promotes the transition of leukocytes in the focus of inflammation;
- stimulates peristalsis and secretory activity of gastrointestinal mucosa cells;
- stimulates contractility of the uterus and fallopian tubes, participates in the process of ovulation, providing follicle rupture;
- prolongs the duration of sexual intercourse in men by delaying ejaculation.
Serotonin is also called a “neurotransmitter (hormone) of good mood” because its production increases during euphoria and decreases with depressed mood. Serotonin is also responsible for self-control (emotional stability). For the production of serotonin, the body needs ultraviolet rays, so in winter, when solar radiation is less, some people are in a depressed mood and tend to be irritated over trifles (it is in a depressed mood, not in a state of depression, because from a medical point of view, depression is a type of mental disorder).
The hormone serotonin is produced by different cells “at the place of demand”, and not by some special organ, but it is produced by some cells, and acts on others.
Now let’s look at the synapse, with a “springboard”, which are neurotransmitters. There they are born and there they die.
“Synapse” is a specialized intercellular contact, through which the cells of the nervous system transmit to each other or other, not nervous, cells signal (nerve impulse). The name comes from the Greek word “synapsis” meaning “connection”.
Excitation spreads through the nerve cell in the form of an electrical impulse. In the synapse region are the so-called” synaptic vesicles”, organoids (so-called cellular organs), capable of producing either a neurotransmitter or an enzyme, this neurotransmitter destroying.
The electrical impulse stimulates the bubbles that produce the neurotransmitter. The neurotransmitter enters the synaptic slit and acts on the membrane of another cell, changing its electrical potential, that is, creating a new electrical impulse.
The release of a neurotransmitter stimulates the bubbles that produce destructive enzymes. Once the neurotransmitter has done its job – triggered the impulse, it is no longer needed.
If you’re interested in how a neurotransmitter creates an impulse, know that it does so by altering the permeability of the cell membrane to positively charged potassium and sodium ions. As a result of the movement of ions change the electrical potentials on the inner and outer sides of the membrane – that’s you and the pulse.
From an electrochemical point of view, a synapse is a site where electrical signals are converted into chemical signals and back – chemical signals into electrical signals.
With synapse, we end here and move on to neurotransmitters, “magic” substances that control the main functions of the body, such as movement, sleep, thinking, emotional reactions, the ability to feel pain.
By chemical nature neurotransmitters are divided into amino acids, peptides and monoamines.
What are amino acids, you already know – a chemical compound in the molecule which simultaneously contains carboxyl (-soon) and amine (- NH2) group.
In everyday life, all peptides are called “proteins”. Chemists call peptides all substances consisting of amino acid residues, and those peptides whose molecules contain 50 or more amino acid residues, called “proteins”. Neurotransmitter molecules have not grown to be called proteins, they contain less than 50 amino acid residues, some-only five. Neurotransmitters “by definition” cannot have very large molecules, because, firstly, they must easily and simply leave the cell, and secondly, they must quickly synthesize in response to an electrical impulse. High-molecular substances pass through cell membranes “with difficulty”, relatively slowly, and their production is a long time.
Monoamines are substances containing one amine group (- NH2).
Also, neurotransmitters can be divided into two groups according to the nature of their actions – exciting and inhibitory. But this separation is not quite correct, because some neurotransmitters (dopamine, acetylcholine) have a dual effect.
Excitatory neurotransmitters are natural stimulants that increase the probability of transmitting an exciting signal. They accelerate the processes of thinking, make us fast and strong, provide muscle contractions of our organs.
Any excitement leads to exhaustion. Working cells should get time to rest, that is, to replenish the resources spent in the course of work. Otherwise, exhaustion will lead to cell death. In addition, in the process of normal functioning of the body, contractions of all muscles should alternate with their relaxation. What is walking or running? Alternating contraction and relaxation of the muscles of the lower extremities. If the contracted muscle does not relax, there is a muscle spasm, the muscle “cramps”. Spasmodic muscle does not work, that is, can not perform its function.
By the way, if we are talking about seizures. Do you know why muscles cramp during intensive work, for example-during swimming? The fact that this spazmirovannah condition tired the muscle is “resting.” In a state of relaxation, it is, of course, “resting” even more fully.
If the heart muscle does not relax after the contraction, the heart cavities will not be filled with a new portion of blood, that is, the heart will stop pumping blood.
Spasm of intestinal muscles will lead to the fact that the movement of food masses in the gut will stop.
Excessive excitation of the nervous system leads to a feeling of anxiety, increased irritability, sleep disorders, and sometimes fainting and seizures.
And so on…
As you know, stimulating neurotransmitters must necessarily be “balanced” in the body by inhibitory neurotransmitters. If there’s a switch, there’s got to be a switch, right? Inhibitory neurotransmitters reduce the probability of transmitting an exciting signal. This provides a balance between excitation and inhibition.
Now let’s get acquainted with specific neurotransmitters.
We start the acquaintance with acetylcholine.
Acetylcholine is a monoamine whose main task is to transfer excitation from nerve cells to muscle cells. The main, but not the only. Acetylcholine also provides impulse transmission to glandular cells and participates in impulse transmission from one nerve cell to another. The body has different receptors for acetylcholine (Yes, neurotransmitters also act through special receptors). Connecting with the same receptors, acetylcholine has an excitatory action, connecting with others inhibitory. Actually, the ambiguity of the neurotransmitter is determined by the presence of receptors of different types.
For example, acetylcholine lowers the heart rate and relaxes the muscles of the walls of peripheral blood vessels, but stimulates peristalsis, increases the reduction of the muscles of the bronchi, uterus, gallbladder and bladder, as well as the circular muscle of the iris (ie – narrows the pupil).
Acetylcholine is very important for our higher nervous activity as it improves memory and increases learning ability. According to one (the oldest) hypothesis, a disease such as Alzheimer’s disease [23] is caused by a decrease in acetylcholine production in certain areas of the brain. In our time, this hypothesis is questioned, but a convincing replacement for it has not yet been found. It may turn out that in Alzheimer’s disease, the failure does not occur at the level of acetylcholine production, but somewhere else. But there is no doubt that acetylcholine can be called a “memory hormone” or a “learning hormone”.
And acetylcholine stimulates the entire nervous system as a whole. Since it improves the conduct of impulses in nerve cells, it can not be otherwise. Some acetylcholine antagonists (for example, the drug amizil) are psychotropic drugs that have a calming effect.
The stimulating effect of acetylcholine depends on its amount. It would seem that the more neurotransmitter is in the synaptic slit, the stronger the impulse it will create. But no – in large doses, acetylcholine blocks the transmission of excitation in synapses, by equalizing the electrical potentials of the outer and inner surfaces of cell membranes. If the potentials inside and outside are the same, no pulse can occur, since the pulse occurs due to the difference in electrical potentials, when the outer surface of a certain section of the membrane becomes negatively charged with respect to the positively charged inner surface. Difference!
All readers probably know what trichlorfon, dichlorvos or Malathion. Poisons used to control harmful insects. Such poisons are called “insecticides”. But the words “sarin” or “zoman” are not known to everyone. Sarin and soman is a potent poison gases nervously-paralytic action, chemical weapons. Do you know what all these poisons have in common? All of them inhibit, that is, bind, the enzyme acetylcholinesterase, which provides the cleavage of acetylcholine after the transmission of the pulse. As a result, excessive amounts of acetylcholine accumulate in the synaptic slits, which first causes continuous generation of exciting signals that are transmitted to the organs and skeletal muscles. Excessive tension that has developed throughout the body, including the excitation of the nervous system, after blocking the transmission of impulses in synapses is replaced by paralysis of the body. All organs stop working, and the body dies.
Other important neurotransmitters that improve memory and learning along with acetylcholine are glutamic acid (one of the amino acids) and its derivative glutamine.
All readers of this book are of course familiar with another derivative of glutamic acid – its sodium salt, called “sodium glutamate” and known as” flavor enhancer ” [24].
“Along the way” glutamic acid is a chemical precursor of gamma-aminobutyric acid, and is also involved in the synthesis of serotonin.
Dopamine, which is also called “dopamine”, as you already know, is a neurotransmitter responsible for good mood, or rather – for the feeling of satisfaction. When we are satisfied, dopamine production in the brain increases. It is stimulated by certain drugs (cocaine, opiates, nicotine, ethyl alcohol). At the heart of all bad habits is the desire to get more dopamine for the brain.
Thoughtful readers may wonder-why no one drinks a solution of dopamine instead of vodka or does not introduce such a solution to himself intravenously for pleasure? Remember that dopamine is not able to penetrate the blood-brain barrier that separates the circulatory and Central nervous systems.
In very large quantities, dopamine causes nervous system arousal, which interferes with concentration and thinking, impairs memory and learning ability.
Elderly people often have a lack of pleasure from activities that previously gave this pleasure. The reason is the age-related decline in dopamine production in the brain.
And if, for example, reduced production of dopamine in the area of the cerebral cortex, exercising control over the movement of body parts, then develops Parkinson’s disease, also called “tremor paralysis”, because it is observed uncontrolled tremor – trembling limbs.
Adrenaline and norepinephrine, the precursor of which is dopamine (all of them are chemically monoamines), are also able to influence our psycho-emotional state. Both excite the nervous system, increase concentration, improve memory, and increase sexual arousal. I want to exclaim: “Oh, what good fellows! Of all trades master!»
Excessive amounts of adrenaline and norepinephrine can cause anxiety, sleep disorders, increased irritability. Lack of adrenaline leads to apathy, indifference to the environment, inhibition of all higher nervous activity. Why does a person become apathetic for a while after stress? Because the supply of adrenaline in the body is depleted.
And do you know why the moments of the strongest emotional experiences sink into the memory for life, and borderline (previous or subsequent) events that occurred against the background of calmness, are soon forgotten? What is the” switch ” of memorization?
Recent studies have shown that this” switch ” is norepinephrine. It helps the parts of the brain occupied with storing information to distinguish the most important and, therefore, the most valuable experience from the less valuable. The body” thinks ” logically-once this experience has caused so many emotions, therefore, it must be stored in long-term memory, and the one that did not cause any reaction, you can safely “erase” from short – term memory-it will never be useful. Thus, norepinephrine released during emotional arousal forms a link between emotions and memory.
Why do you think interest in learning increases the effectiveness of learning? Consciousness, responsibility and high motivation – it goes without saying, no one disputes, but plays a role and the level of emotions manifested by a person during training. An interested student perceives the learning process more emotionally, and therefore he has much more success than a disinterested student who learns “from under the stick”.
Moreover-norepinephrine increases the number of membrane receptors, which bind neurotransmitters in nerve cells, providing the formation of memory. That is, in fact, has a General stimulating effect on these cells, improves – strengthens and accelerates – the conduct of nerve impulses by them. The honorary title of “main memory hormone” can be assigned to noradrenaline without question.
In our body there is a group of neurotransmitters-peptides, which in their biochemical action similar to morphine and its analogues. These neurotransmitters are called “endorphins”, which means”internal morphines”. Endorphins are also produced in the pituitary gland during stress, that is, they are stress hormones, but we did not consider them in the corresponding Chapter, because they do not belong to the main, but to the secondary stress hormones. As a stress hormone, endorphins reduce pain sensitivity.
Endorphins – the “happiness neurotransmitters”. They cause euphoria, a sense of bliss, complete satisfaction. Morphine and other drugs of opium, as well as their chemical analogues in the body bind to the same receptors as endorphins, and deliver the same sensations, but to a stronger extent, because they are introduced into the body in large quantities.
Do you know why physical activity is a joy? Not only because it increases the production of dopamine, but also because, perceiving muscle fatigue as stress, the body removes it by increased production of endorphins. The biological meaning of this increase is to reduce the pain in tired muscles, but as a” bonus ” improves mood.
The bliss that comes at the moment of orgasm, partly provide endorphins. And it is believed that they are “responsible” for the pleasure arising from the enjoyment of works of art, that is, for obtaining aesthetic pleasure, so to speak. For the fun of it “prose” responds to the dopamine, and for aesthetic endorphins.
About a quarter of a century ago, another neurotransmitter was discovered-anandamide, whose action coincides with the action of marijuana. Have anandamide – a narrow specialization. He is involved in the elimination of negative emotions associated with past experiences. That is, if you tend to often and strongly worry about the events of bygone days, the reason for this may be insufficient production of anandamide, ” neurotransmitter of oblivion.” The name is not very accurate, since memory is not affected by anandamide, but the essence of it reflects.
Serotonin has already been mentioned, so we will not repeat ourselves, but consider the three circumstances associated with this neurotransmitter.
First, estrogens stimulate the production of serotonin. When the concentration of estrogen in the blood decreases, serotonin is produced less. Here is another reason for the depressed mood and increased irritability that occur in women in the period preceding menstruation, as well as during menopause.
Second, frequent stress depletes serotonin reserves in the body. So the more nervous you are, the more irritable you become. There is such a vicious circle.
Third – serotonin itself the sensation of hunger.
The” enemy “of serotonin is the already familiar epiphysis hormone melatonin, which stimulates the production of a neurotransmitter called”gamma-aminobutyric acid.” Gamma-aminobutyric acid, in turn, inhibits the production of serotonin.
A remarkable fact-serotonin is a chemical precursor of melatonin. Sometimes the” kinship ” of hormones are intertwined in the most incredible way.
Melatonin prepares the body to fall asleep. Being in a depressed mood, many people suffer from insomnia. They can not sleep, because in this state the level of serotonin in the body falls and there is nothing to synthesize melatonin.
Gamma-aminobutyric acid is the main and most important inhibitory neurotransmitter of our body. It has a calming effect, because it prevents the action of exciting mediators-adrenaline, norepinephrine, dopamine and serotonin, preventing excessive excitation of the Central nervous system. Gamma-aminobutyric acid can rightly be called a ” neurotransmitter of peace.”
It is believed that people with a congenital deficiency of this acid have a predisposition to alcoholism, because they can try to achieve a relatively “deficit” for them a sense of relaxation with ethyl alcohol.
To what has already been said about oxytocin, the female “neurotransmitter of trust” and the male “neurotransmitter of critical attitude”, as well as one of the “neurotransmitters of orgasm”, there is nothing to add. Except that, according to the latest data, its output increases when tactile contact – touching, stroking, etc. Here’s another brick in the Foundation of the well-known postulate, which States that long foreplay (stroking, bodily contact) has a positive effect on power and brightness orgasm.
Phenylethylamine, which increases the concentration of dopamine and norepinephrine in the intersynaptic spaces, is often called “love neurotransmitter” or “love neurotransmitter”, but this is not entirely true, because phenylethylamine is “responsible” for the emergence of attraction, not love. When a person meets an attractive partner, his brain begins to produce phenylethylamine. Thanks to phenylethylamine, the formation of primary attraction in humans is primarily due to visual impression, not smell, as in the vast majority of mammals. Phenylethylamine is also produced when thinking about an attractive person. So it would be more correct to call this neurotransmitter ” the neurotransmitter of attraction»
Phenylethylamine can also be called a “attention neurotransmitter” because it promotes concentration.
Help phenylethylamine pheromones-products of external secretion, attracting individuals of the opposite sex. In humans, they are produced by the skin of the nasolabial folds, chest glands, anal-genital area and armpits, as well as the mucous membrane of the vagina. The effect of pheromones is due to physiology and nothing more. The number of pheromones is directly proportional to the strength of the attraction they cause. And the perception of the visual image as attractive is a complex psychological process.
This would be the end of our acquaintance with the main neurotransmitters that shape our mood and participate in the processes of higher nervous activity. But I would like to talk about one more substance, which, first, is inorganic, not organic [25], like all other neurotransmitters, and secondly, does not take a direct, but indirect part in the formation of mood. But, nevertheless, this substance is very important and deserves attention.
This substance is nitrogen monoxide (NO) or nitric oxide, a neurotransmitter involved in the formation of long-term memory and has a pronounced vasodilating effect. It is nitrogen monoxide that provides an erection, so it can rightfully be considered a neurotransmitter responsible for good mood, and not only in men, but also in women too.
What is an erection from a physiological point of view?
The male brain receives sexual stimulation (visual, tactile, olfactory, auditory, mental or composite). With the help of neurotransmitters such as noradrenaline, acetylcholine and oxytocin, the nerve impulse is transmitted from the brain to the muscles of the cavernous bodies of the penis.
The joint work of nerve impulses and testosterone causes the release of nitrogen monoxide in the synapses of the muscles of the cavernous bodies.
Nitrogen monoxide, in turn, causes the formation of a substance with a complex name for the uninitiated-cyclic guanosine monophosphate. Instead of this ear-scratching name, we will continue to use the “official” abbreviation-cGMP.
cGMP causes relaxation of muscle cells of cavernous bodies, which are filled with blood-there is an erection. Blood-filled cavernous bodies constrict the veins that divert blood from the penis, which allows you to maintain the penis in an erect state.
What do drugs really improve potency? (The key word is “real,” not tiger bile or, say, crushed Rhino horn.) Some contain an inhibitor (suppressor) of the enzyme that cleaves cGMP, while others stimulate the production of nitrogen monoxide in cavernous bodies.
And in the end-a few words about the ubiquitous triiodothyronine, which is produced in the thyroid gland. This universal (do not be afraid of the word) stimulant, acting on almost all cells of our body, has an impact on the cells of the nervous system. The lack of triiodothyronine, which occurs with a decrease in thyroid function, turns a person into a sluggish apathetic slow-witted. About “slow-witted” mentioned not for the sake of a red word, and in strict accordance with reality. Triiodothyronine stimulates the brain, that is-takes part in the development of mental abilities and maintaining them at the proper level, as well as provides emotional stability. Any endocrinologist with experience is able to tell a lot of stories about how the damage to the character (that is, sharply increased irritability) people explained various reasons for everyday nature, and in the end it turned out that life had nothing to do with it, it was an increased concentration of triiodothyronine in the blood.
With a chronic lack of thyroid hormones in children develops such a disease as cretinism (if someone does not know, then “cretin”, “idiot” and “moron” is not only swearing, but also medical diagnoses, but “fool” and “fool” – swearing and nothing more). Cretinism, by the way, is accompanied by a delay not only mental but also physical development.
Excessive production of thyroid hormones makes a person irritable, restless, forgetful, unable to focus on something specific for a long time. It would seem that if the lack of thyroid hormones lowers mental abilities, the excess should do the opposite – to develop intelligence in every possible way. But this does not happen, because excessive stimulation has on all cells of the body as adverse effect as insufficient, only, so to speak, “with the opposite sign.” But, as you know, horseradish radishes are not sweeter.
Recently, there was a version that thyroid hormones are involved in the formation of social memory, that is, memory, due to communication with other people, the accumulation of experience gained by the body as a part of society. But so far, this version is awaiting confirmation. I must say that the study of the higher nervous activity of man is, figuratively speaking, the land of the unknown and the untilled field, as a secret there is still much more than open.
Summary
In our body there are biologically active substances involved in the transmission of electrochemical impulse from one nerve cell to another, as well as from nerve cells to other cells, for example – to muscle or glandular. These substances are called “neurotransmitters”or ” neurotransmitters”.
Serotonin is a neurotransmitter of good mood and emotional stability.
Acetylcholine is a neurotransmitter of memory and learning, as well as a stimulant of the entire nervous system, which improves the conduct of impulses in nerve cells.
Glutamic acid and its derivative glutamine are also neurotransmitters of memory and learning.
Dopamine – dopamine) is a neurotransmitter of satisfaction and a stimulant of the nervous system.
Adrenaline and norepinephrine excite the nervous system, increase concentration, improve memory, and increase sexual arousal. Given how norepinephrine stimulates long-term memory and generally on the totality of merit, it can be called ” the main memory hormone.”
Endorphins are neurotransmitters of happiness and bliss; they take part in the formation of sensations such as orgasm, and form the pleasure that occurs when enjoying works of art (aesthetic pleasure).
Anandamide is a neurotransmitter of oblivion, it is involved in the elimination of negative emotions associated with past experiences.
Gamma-aminobutyric acid is the main and most important inhibitory neurotransmitter of our body, the neurotransmitter of tranquility.
Oxytocin for women is a neurotransmitter confidence for men neurotransmitter critical attitude, as well as one of the neurotransmitters orgasm for both sexes.
Phenylethylamine is a neurotransmitter of attraction and attention.
Inorganic substance nitrogen monoxide – nitric oxide) is a neurotransmitter of erection and long-term memory.
Thyroid hormone triiodothyronine, which is a universal stimulant that acts on almost all cells of our body, and affects the cells of the nervous system. Triiodothyronine takes part in the development of mental abilities and maintaining them at the proper level, as well as provides emotional stability.
CAUTION
Any knowledge, dear readers, can bring both benefit and harm just as one and the same knife can cut sausage, and it is possible and veins with arteries. The author considers it his duty to warn all who have read this Chapter that experiments with artificial control of mood and mental abilities by any means will do you nothing but harm, because they can not do anything else.