A hormone is a biologically active substance produced by the human endocrine system, which includes the pituitary gland, thyroid gland, adrenal glands and a number of special cells. Hormones regulate all physiological processes in the body, while not directly contacting the cells, but working with them through special receptors tuned to the corresponding hormone. Which organs are involved in hormonal regulation, and how it affects the body - that is the main question.
Classification by origin
The mechanism of hormonal regulation includes a variety of functions. This is possible due to the fact that hormones are composed of a variety of substances. Conventionally, they can be divided into several groups according to composition:
- Hormones, consisting mainly of protein, are called polypoids and are produced mainly in the hypothalamus, pituitary and thyroid glands. Also this type of hormonesproduced in the pancreas.
- Another group of hormones is mostly made up of amino acids. This type of trace elements is produced in the adrenal glands and the thyroid gland, that part of it, which is called iodine.
- Steroid type of hormones. It is produced by the human reproductive system - in the female body by the ovaries, and in the male - by the testicles. Also, a small proportion of steroid hormones is produced in the adrenal cortex.
Classification by function
These trace elements are involved in the hormonal regulation of various processes in the body. For example, lipid, carbohydrate and amino acid metabolism is regulated by insulin, glucagon, adrenaline, cortisol, thyroxine and growth hormone.
The exchange of s alt and water in the human body is supported by aldosterone and vasopressin.
Calcium and phosphates are absorbed by body cells with the help of parathyroid hormone, calcitonin and calcitriol. Hormones such as estrogen, androgen, gonadotropic hormones work in the reproductive system.
There are trace elements that regulate the production of other hormones - these are the tropic hormones of the pituitary gland, liberin and statin in the hypothalamus. But hormonal regulation involves the use of the same trace elements in various processes, for example, testosterone regulates the functioning of the reproductive system in a man's body, while it is also responsible for the growth of bones and muscle mass. And without adrenaline, the work of the cardiovascular system and the regulation of the quality of absorption of carbohydrates and lipids by the body is impossible.
The mechanism of action of hormones on the body
The mechanism of hormonal regulation involves several types of hormone effects on the cell. The first way is to influence the activity of enzymes in the cell through a membrane receptor. At the same time, the hormone itself does not penetrate the cell, but acts on it through special intermediaries - receptors. These types of effects include peptides, protein hormones and adrenaline.
In the second method of exposure, hormones pass through the membrane into the cell and directly affect their respective receptors. These are steroids and thyroid hormones.
In the third group of hormones are insulin and thyroid hormones, they act on membrane receptors, using changes in ions in membrane channels.
What is the uniqueness of the hormonal effect?
Hormonal regulation is unique in that it is carried out almost instantly and at the same time uses a very small amount of active substance. The level of hormones in the blood is measured in micromoles.
Another feature is distancing: homon can be produced only in one gland, while getting into the organ of influence located in another part of the body.
And the last, very rare and convenient function of hormonal regulation is the rapid inhibition of the process. The body does not wait until the active element removes the natural metabolism from the body, it produces an inactivating hormone. It stops the action of the active hormone almost instantly.
What is a receptor and signal transduction across a membrane?
Hormonal regulation of metabolism is carried out by the action of hormones on receptors that are sensitive to them, located inside cells or on their surface - on the membrane. A receptor sensitive to a certain hormone makes the cell a target.
The receptor is similar in structure to the hormone of action, and it consists of complex proteins of glycoproteins. This element usually consists of 3 domains. The first is the hormone recognition domain. The second is a domain that conducts through the membrane. And the third creates a connection with the hormone with cellular substances.
The hormonal regulation system is divided into several steps:
- Receptor binding to the corresponding hormone.
- The receptor-hormone bond reacts with the G-protein, changing its structure.
- The resulting hormone-receptor protein bond causes an adenylate cyclase reaction in the cell.
- At the next step, adenylate cyclase causes a protein kinase reaction, which accordingly leads to the activation of protein enzymes.
This hormonal regulation of functions is called the adenylate cyclase system.
There is another system - guanylate cyclase. According to the principle of regulation of the hormonal cycle, it is similar to the adenylate cyclase system, but during its operation, the signal from the sequence of effects on proteins in the cell can be amplified tenfold. There are also similar signaling methods - Ca2+-messenger system and inositol triphosphate system. Each individual type of protein has its own system.
Intracellular receptors
There isa number of hormones, mostly steroids, that can act on the target cell by coming into contact with receptors located in the cytoplasm, that is, inside the cell. In this case, the hormone immediately penetrates to the cell nucleus and, having entered into contact with the receptor, triggers the mechanism of action on the DNA enhancer or silencer. This ultimately leads to a change in the amount of proteins and enzymes that affect the metabolism inside the cell and change its state.
CNS hormones
It is known that some hormones are produced by the central burrow system, namely the hypothalamus - these are tropic hormones. Neurohormonal regulation accumulates them in the anterior and posterior parts of the hypothalamus, from where they enter the thyroid gland with the bloodstream.
Hormones such as thyrotropin, corticotropin, somatotropin, lutropin, prolactin and a number of others have a very wide range of effects on the human body. At the same time, hormones that inhibit their action are produced in the thyroid gland in response to a nervous reaction by the periphery of organs. But even if this did not happen, this type of hormone has the shortest period of life - no more than 4 minutes.
Thyroid hormones
Hormonal regulation of the body is not complete without the thyroid gland. It produces such hormones that are responsible for the absorption of oxygen by the cells of the body, synthesize a number of proteins, secrete cholesterol and bile, and also break down fatty acids and the fats themselves. ittriiodothyronine and tetraiodothyronine.
When the level of these hormones in the blood increases, the breakdown of proteins, fats and carbohydrates accelerates, the heart rate accelerates, the work of the entire nervous system is loosened and goiter is possible.
With low production of triiodothyronine and tetraiodothyronine in the body, failures of a different nature occur - a person's face becomes rounded, mental and physical development of the child is delayed, metabolism slows down.
Algorithm for the regulation of hormones by the central nervous system
All functions in the body are controlled by the human brain. Moreover, this always happens unconsciously, that is, without the participation of the personal "I" of a person.
Even the hormonal regulation of glucose or other substances in human blood is a signal passing from an external stimulus or internal organ to the central nervous system.
When a signal is received, the hypothalamus, located in the diencephalon, enters the process. The hormones produced by it enter the pituitary gland, where pituitary hormones, that is, tropic hormones, are already synthesized. From the anterior lobe in the pituitary gland, the rush hormone enters the thyroid gland or other organs of the endocrine system. There they trigger the synthesis of hormones appropriate to the situation.
This chain of levels of hormonal regulation can be seen on the example of adrenaline.
In case of a strong fright, that is, external influence, the whole chain instantly starts to work, the hypothalamus - pituitary gland - adrenal glands - muscles. Once in the blood, adrenaline causes an increased contraction of the heart muscle, which means thatincreased blood flow to the muscles. This makes them stronger and more resilient. This explains the fact that a person in the background of a strong fright can run a distance faster than a trained athlete or overcome a rather high obstacle in one jump.
What affects the amount of hormones in the blood?
Hormones are constantly present in the blood, but in some periods they are less, and in some more. It depends on many factors. For example, chronic nervous tension, stress, fatigue, lack of sleep. The quality and quantity of food eaten, alcohol consumed or cigarettes smoked also affects the level of hormones. It is known that in the daytime the level of hormones is the lowest compared to the night. Especially its peak is reached in the early morning. By the way, this is why men have a morning erection, and this is why all tests for the level of a particular hormone are taken in the morning and on an empty stomach.
In the case of female hormones, their blood levels are affected by the day of the monthly cycle of menstruation.
Types of hormones according to their effects on the body
Hormones and hormonal regulation depend on the type of trace element. After all, there are hormones whose life lasts less than 4 minutes, and there are those that affect the body for 30 minutes and even several hours. Then a new stimulation is needed to produce them.
- Anabolic hormones. These are trace elements that allow the body to receive and store energy in cells. They are produced by the pituitary glandthey are represented by follitropin, lutropin, androgens, estrogens, somatotropin and chorionic gonadotropin of the placenta.
- Insulin. This hormone is produced by the beta cells of the pancreas. Insulin controls the uptake of glucose by cells in the body. When this organ malfunctions and the production of insulin stops, a person develops diabetes mellitus. The disease is incurable, and if not properly treated, it can even be fatal. Fortunately, it is easily diagnosed by primary symptoms and elementary blood tests. So if a person began to drink a lot, he was constantly thirsty, and urination became repeated, then, most likely, his blood sugar level was disturbed, which means that he has diabetes. Insulin-dependent diabetes is most often a congenital pathology, and type 2 diabetes, respectively, is an acquired disease. Treatment includes insulin injections and a strict diet.
- Catabolic hormones are represented by corticotropin, cortisol, glucagon, thyroxine and adrenaline. These trace elements participate and manage the breakdown of fats, amino acids and carbohydrates that have entered the body with food, and the production of energy from them.
- Thyroxine. This hormone is produced in the thyroid gland - in that part of it that synthesizes iodine cells. The hormone controls the production of a wide variety of hormones, mainly sex, and regulating the growth of tissues in the body.
- Glucagon polypeptide stimulates the breakdown of glycogen, which raises blood sugar levels.
- Corticosteroid. This type of hormone is produced mainly inadrenal glands and is presented in the form of a female hormone - estrogen and a male hormone - androgen. In addition, corticosteroids perform a number of other functions in metabolism that affect its growth and feedback to the central nervous system.
- Adrenaline, norepinephrine and dopamine are a group of so-called catecholamines. It is difficult to overestimate the influence of these trace elements on the functioning of the body as a whole and in particular on its cardiovascular system. After all, it is adrenaline that helps the heart to smoothly and smoothly pump blood through the vessels.
Hormones are produced not only by certain organs of the endocrine system, there are also specific cells capable of synthesizing these trace elements. For example, there is a neurohormone produced by nerve cells, or the so-called tissue hormone, which is born in skin cells and has a purely local effect.
Conclusion
Hormonal regulation depends on many factors, and the absence or low level of just one hormone can lead to a dangerous condition in the body. Using insulin as an example, diabetes mellitus was considered, and if there is almost no testosterone in a man’s body, then he will never be able to become a father, while he will be undersized and weak. Just like a woman without the required amount of estrogen will not have external sexual characteristics and will lose the ability to give birth to children.
Thus, the question arises - how to maintain the necessary level of the right hormones in the body?
First of all, you should not let the appearance of alarming signs in the work of the body - incomprehensible thirst, pain inthroat, sleep and appetite disturbances, dry flaky skin, fading hair and lethargy. If these symptoms appear, you should immediately consult a doctor. And children should be shown to the pediatrician at least every 6 months. Indeed, many dangerous pathologies manifest themselves precisely in childhood, when it is still possible to cope with the disease with the help of substitution therapy. An example of such a deviation is gigantism or dwarfism.
Adults need to pay attention to their lifestyle. You can not accumulate fatigue and stress - this necessarily leads to hormonal failure. In order for the central nervous system to work without interruption, you need to learn not to respond to stimuli, go to bed on time. Sleep should be at least 8 hours a day. Moreover, you need to sleep at night, since some of the hormones are produced only in the dark.
We must not forget about the dangers of overeating and addictions. Alcohol can destroy the pancreas, and this is a direct path to diabetes and early death.
Throughout life, you need to follow a certain diet - do not eat fatty and sweet, reduce the consumption of preservatives, diversify your menu with fresh vegetables and fruits. But most importantly, you need to eat fractionally - 5-6 times a day in small portions.
