The importance of the kidneys in the human body. The structure and function of the kidneys in the human body, renal pathologies, rules for the treatment and prevention of diseases of important organs of the urinary system

The kidneys are one of the vital organs in the human body, they perform more than one function. Metabolic, protective, excretory, homeostatic and endocrine are the functions of the kidneys. At healthy person a pair of kidneys, although there are cases when one of the kidneys is removed under the threat of life, then throughout the life of the patient, his health is at risk.

Throughout the day, the kidneys pass through themselves all the blood that is in the body. In one minute, one liter of blood passes through the kidneys, from this blood the kidneys select all the harmful substances that should go to the blood plasma, after which the harmful microbes enter the ureter, and only after that they end up in the bladder. When a person defecates, harmful substances are excreted from the human body along with urine.

Thanks to the valve that is in the ureter, the toxins cannot go back because it only opens in one direction. During the day, the kidneys pump about 200 liters of blood through themselves, thereby removing toxins from the body and making the blood sterile. And this, you see, is a very important function for human health and life, which is the main one.

Also in the kidneys is the synthesis of essential hormones, such as renin, erythropoietin and prostaglandin. Water in the human body is retained due to the hormone renin, prostaglandin regulates blood pressure, and the number of red blood cells is regulated by erythropoietin.

In the kidneys, the synthesis of various vitamins and microelements takes place, without which human life is not possible. Thanks to the ability of the kidneys to synthesize in the body, the balance of carbohydrates, proteins and lipids is maintained.

Summing up, we can say that the kidneys perform such functions in the body, without which further human life is not possible. Therefore, everyone should protect the kidneys and the health of the whole organism.

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The kidneys are of great importance in the human body. They perform a number of vital functions. Humans normally have two organs. Therefore, there are types of kidneys - right and left. A person can live with one of them, but the vital activity of the organism will be under constant threat, because its resistance to infections will decrease tenfold.

The kidney is a paired organ. This means that normally a person has two of them. Each organ is bean-shaped and belongs to the urinary system. However, the main functions of the kidneys are not limited to the excretory function.

The organs are located in the lumbar region on the right and left between the thoracic and lumbar spine. The location of the right kidney is slightly lower than the left one. This is due to the fact that above it is the liver, which prevents the kidney from moving upward.

The kidneys are approximately the same size: they are 11.5 to 12.5 cm long, 3 to 4 cm thick, 5 to 6 cm wide, and weigh 120 to 200 g. The right one is usually slightly smaller. .

What is the physiology of the kidneys? The organ is covered with a capsule from the outside, which reliably protects it. In addition, each kidney consists of a system whose functions are reduced to the accumulation and excretion of urine, as well as of the parenchyma. The parenchyma consists of the cortex (its outer layer) and the medulla (its inner layer). The urinary storage system is the small renal calyces. The small calyces fuse to form the large calyces. The latter are also connected and together form the renal pelvis. And the pelvis is connected to the ureter. In humans, respectively, there are two ureters that enter into bladder.

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In addition, the organs are equipped with a structural and functional unit called the nephron. The nephron is considered the most important unit of the kidney. Each of the organs contains more than one nephron, but has about 1 million of them. Each nephron is responsible for the functioning of the kidneys in the human body. It is the nephron that is responsible for the process of urination. Most of the nephrons are located in the cortex of the kidney.

Each structurally functional unit of the nephron is a whole system. This system consists of the Shumlyansky-Bowman capsule, the glomerulus, and the tubules that pass into each other. Each glomerulus is a system of capillaries that supplies blood to the kidney. Loops of these capillaries are located in the cavity of the capsule, which is located between its two walls. The cavity of the capsule passes into the cavity of the tubules. These tubules form a loop penetrating from the cortex into the medulla. In the latter there are nephron and excretory tubules. Urine is excreted through the second tubules into the cups.

The medulla forms pyramids with apexes. Each top of the pyramid ends with papillae, and they enter the cavity of the small calyx. In the area of the papillae, all excretory tubules unite.

The structural functional unit of the kidney, the nephron, ensures the proper functioning of the organs. If the nephron were absent, the organs would not be able to perform the functions assigned to them.

The physiology of the kidneys includes not only the nephron, but also other systems that ensure the functioning of the organs. So, the renal arteries depart from the aorta. Thanks to them, the blood supply to the kidney occurs. Nervous regulation of organ function is carried out with the help of nerves that penetrate from the celiac plexus directly into the kidneys. The sensitivity of the capsule of the kidneys is also possible due to the nerves.

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To understand how the kidneys work, first of all, you need to understand what functions are assigned to them. These include the following:

excretory, or excretory;
osmoregulatory;
ion-regulating;
intrasecretory, or endocrine;
metabolic;
hematopoietic (takes a direct part in this process);
concentration function of the kidneys.

During the day, they pump the entire volume of blood. The number of repetitions of this process is huge. About 1 liter of blood is pumped in 1 minute. At the same time, the organs select from the pumped blood all decay products, toxins, microbes and other substances harmful to the human body. Then all these substances enter the blood plasma. Then all this is sent to the ureters, and from there to the bladder. After that, harmful substances leave the human body when emptying the bladder.

When toxins enter the ureters, there is no way back into the body. Thanks to a special valve located in the organs, the re-entry of toxins into the body is absolutely excluded. This is made possible by the fact that the valve opens in only one direction.

Thus, pumping over 200 liters of blood per day, the organs guard its purity. From slagged with toxins and microbes, the blood becomes clean. This is extremely important, since blood bathes every cell of the human body, so it is vital that it be cleansed.

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So, the main function that organs perform is excretory. It is also called excretory. The excretory function of the kidneys is responsible for filtration and secretion. These processes occur with the participation of the glomerulus and tubules. In particular, the filtration process is carried out in the glomerulus, and the processes of secretion and reabsorption of substances that need to be removed from the body are carried out in the tubules. The excretory function of the kidneys is very important, as it is responsible for the formation of urine and ensures its normal excretion (excretion) from the body.

The endocrine function consists in the synthesis of certain hormones. First of all, this concerns renin, due to which water is retained in the human body and the volume of circulating blood is regulated. The hormone erythropoietin is also important, which stimulates the creation of red blood cells in the bone marrow. Finally, organs synthesize prostaglandins. These are substances that regulate blood pressure.

The metabolic function lies in the fact that it is in the kidneys that microelements and substances vital for the functioning of the body are synthesized and transformed into even more important ones. For example, vitamin D is converted to D3. Both vitamins are essential for humans, but vitamin D3 is the more active form of vitamin D. This function also maintains an optimal balance of proteins, carbohydrates and lipids in the body.

The ion-regulating function implies the regulation of the acid-base balance, for which these organs are also responsible. Thanks to them, the acid and alkaline components of blood plasma are maintained in a stable and optimal ratio. Both organs secrete, if necessary, an excess of bicarbonate or hydrogen, due to which this balance is maintained.

The osmoregulatory function is to maintain the concentration of osmotically active blood substances under various water regimes to which the body may be exposed.

The hematopoietic function means the participation of both organs in the process of hematopoiesis and blood purification from toxins, microbes, harmful bacteria and toxins.

The concentration function of the kidneys means that they concentrate and dilute urine by excreting water and solutes (primarily urea). The organs must do this almost independently of each other. When urine is diluted, more water is excreted than solutes. On the contrary, concentration releases a larger volume of solutes rather than water. The concentration function of the kidneys is extremely important for the life of the entire human body.

Thus, it becomes clear that the importance of the kidneys and their role for the body is so great that it is difficult to overestimate them.

That is why it is so important to pay due attention to this and consult a doctor at the slightest disturbance in the functioning of these organs. Since many processes in the body depend on the work of these organs, the restoration of kidney function becomes an extremely important event.

Almost all the functions of the kidneys in our body are irreplaceable and vital, and with various violations of their normal work, most organs and systems of the human body suffer. Thanks to the activity of the kidneys, the constancy of the internal environment of the body (homeostasis) is maintained. When any irreversible pathological process occurs in this organ, the consequences of the disease become extremely severe, and sometimes fatal.

If we consider the question of what function the kidneys perform in the human body and what life support processes they control, first of all, it is necessary to get acquainted with the structural features of all components of this organ (especially at the cellular level).

Normally, a person from birth has two kidneys, which are located symmetrically from the spinal column in his thoracolumbar region. If developmental anomalies occur, a child may be born with three or, conversely, one kidney.

The organ has a bean-shaped form, and outside it is covered with a dense capsule, consisting of a connective tissue component. The outer layer is called the cortical substance of the kidney, it occupies a smaller volume. The inner layer is called the "medulla", its basis is parenchymal tissue and stroma, which is abundantly penetrated by renal vessels and nerve fibers.

If we disassemble the process of accumulation of urine, then in a simplified version it looks like this: small cups merge with each other, forming large cups, and those, in turn, form a system of pelvises and open into the lumen of the ureter.

The morphofunctional unit of the kidney is the nephron, which is responsible for most of the functions of the kidneys in the human body. All nephrons are closely interconnected and represent a complex "uninterrupted" mechanism.

In their structure, the following structures are distinguished:

the glomerular apparatus (malpighian body), located in the thickness of the cortical substance, the main function of which is to filter the incoming blood;
a capsule that covers the outside of the glomerulus and acts as a "filter" through which the blood is cleansed of any kind of toxins and metabolic products;
a complex system of convoluted tubules that pass into each other and allow the reabsorption of the filtered fluid.

The tissues of each kidney contain at least 1 million actively functioning nephrons.

The work of all components of the nephron sequentially goes through three phases:

Filtration of blood plasma with the formation of primary urine (occurs in the glomeruli). During the day, approximately 200 liters of such urine is formed through the kidneys, which is close in composition to human plasma.
Reabsorption or the process of reabsorption is necessary so that the body does not lose the necessary substances in the urine (this occurs in the tubular system). Thus, vitamins, salts important to the body, glucose, amino acids and others are retained.
Secretion, in which all toxic products, unnecessary ions and other substances that are retained by the renal filter enter the final urinary sediment and are excreted irrevocably.

The work of the renal apparatus occurs in a constant mode, where one phase of the process smoothly replaces another

adrenal glands

When it comes to the structure and function of the kidneys, it is impossible not to mention that at the upper pole of this organ there are special paired formations called the adrenal glands. Despite the fact that they have a small volume, their functionality is unique and extremely necessary.

The adrenal glands consist of parenchyma and belong to a paired endocrine organ, which determines their main purpose in the human body. The oppression of their work leads to a number of serious disorders that require immediate medical intervention. Among the most frequent illnesses, which a specialist has to deal with, distinguish such a pathology as hypofunction of the adrenal glands (the production of certain hormones is sharply inhibited).

The adrenal glands are a vital organ for humans.

Functions of the kidneys and adrenal glands

The main function for which the kidneys are responsible is called excretory - this is the ability to form and, subsequently, excrete the end product of metabolism, namely urine. In the medical literature, one can come across the term "excretory" function, which is synonymous with the previous process.

The excretory (or excretory) activity of the kidneys includes the filtration and secretory functions, which were described above. Their main task is the removal of toxins from the body through urinary sediment.

The final urine contains "unnecessary" waste products of the body

An equally important function of the kidneys is their ability to synthesize hormonal substances. The endocrine work of the body is associated with the entry into the blood of such hormones as:

renin (it is responsible for the balance of water in the body, prevents its excessive release and controls the constancy of blood volume in the circulatory bed);
erythropoietin (a substance that stimulates the production of red blood cells in bone marrow cells);
prostaglandins (control blood pressure).

The metabolic function of an organ lies in the fact that a number of biological substances are synthesized in its tissues or they are converted into active forms (for example, the inactive form of vitamin D in the kidneys changes its structure and becomes more active).

The kidneys are able to maintain the balance of the ionic composition of the plasma and maintain a constant osmotic pressure in the body.

The concentration function of the renal apparatus is that it is capable of concentrating urine, namely, increased excretion of dissolved substrates with it. When there is a failure in this function, then, on the contrary, the release of water increases, and not substances. Thus, the functional ability of the kidneys is reflected.

The most important functions of the adrenal glands are reflected in the following:

They are directly involved in many metabolic and metabolic processes.
They produce a number of vital hormonal substances that affect the functioning of individual body systems (mainly, these are the functions of the adrenal cortex).
Determine the behavior and reaction of the human body to stressful situations.
Thanks to the adrenal glands, the body's response to irritating external influences is formed.

The main function of the adrenal glands is the synthesis of hormonal substances.

Dysfunction

Entire books have been written about the possible factors and causes of dysfunctions in the activity of the kidneys, there are many syndromes, diseases and pathological conditions that are a consequence of a violation of one or another organ function. All of them are undoubtedly very important, but we will try to focus on the most important points.

When it comes to etiological factors, that is, the causes that led to kidney disease, the following groups should be distinguished among them.

Prerenal mechanisms are caused by processes that indirectly affect the functional activity of the organ. These include:

various kinds of mental states, disorders in the work of the nervous system, as a result of which the development of reflex urinary retention is possible, up to its complete absence;
pathology of an endocrine nature, leading to a violation in the synthesis of hormonal substances that can affect the functioning of the kidney;
impaired blood supply to the organ during general hypotensive processes (for example, during collapse) or during a hypertensive crisis.

Renal mechanisms imply direct damage to the tissues of the kidney (inflammatory or autoimmune diseases, thrombosis, aneurysm or atherosclerosis of the renal vessels, and others).

Postrenal damage mechanisms are triggered when obstacles arise in the way of the natural outflow of urine (blockage of the lumen of the ureter by a stone, compression by a tumor process, and others).

The main types of acute renal failure

Development mechanisms

When exposed to any of the above factors, there are violations associated with a change in the processes of filtration, reabsorption or excretion.

Filtration changes can manifest themselves:

a decrease in the volume of filtered plasma in the glomerular apparatus (in hypotonic conditions, necrotic or sclerotic processes in the tissues of the glomeruli);
an increase in the volume of filtered plasma (hypertensive conditions, inflammatory processes leading to increased permeability of the glomerular membrane).

Changes in reabsorption are characterized by a slowdown in this process, which is most often associated with genetic abnormalities at the enzyme level.

Violation of excretion is manifested in the retention of toxic substances in the body and their adverse effects on the entire body, possibly with glomerulonephritis of various etiologies, ischemic kidney disease and others.

The work of the kidneys is evaluated according to the following characteristics:

Indicators of diuresis, that is, the amount of urine excreted during the day. Normally, a person excretes slightly less urine than he drinks liquids, and in case of pathology, the development of polyuria, oliguria or anuria is likely.
The density of the urinary sediment (normal ranges from 1008 to 1028). In pathology, they speak of hyperstenuria, hypostenuria or isosthenuria.
The components that make up urine and their quantitative ratio (we are talking about leukocytes, erythrocytes, protein, cylinders and others).

The functional work of the kidneys is assessed according to a number of diagnostic criteria for urinary sediment.

Renal failure is a complex of symptoms and syndromes, the development of which is due to a decrease or complete cessation of urine output. There is an accumulation of toxic metabolic products that "poison" the body.

An acute process develops literally within a few hours, and its main sign is the progression and disorder of all vital processes.

Chronic insufficiency can develop for many years, this is due to the gradual death of nephrons.

To restore the impaired functions of the renal apparatus, they resort to etiotropic and pathogenetic therapy, but do not forget about symptomatic treatment.

Etiotropic therapy includes the complete elimination or maximum correction of all causes that have become the source of the disease.

The principles of pathogenetic treatment are to block certain links of the disease, which allows you to start the restoration of kidney function and their natural work. For this purpose, drugs are used that can suppress the immune system, or, conversely, stimulate the protective properties of the body, perform hemodialysis procedures and others.

Conducting sessions of hemodialysis blood purification helps the human body fight toxic effects harmful substances and slag

Symptomatic therapy includes a wide range of medicines, restoring and correcting the consequences of improper functioning of the kidneys (antihypertensive, diuretic drugs, and others).

Unfortunately, kidney pathology is very common and affects the able-bodied segments of the population, both among women and men. If functional disorders are not diagnosed in time, then there is a risk of a protracted course of the process, which often causes disability.

One of the important filtration organs in the human body is the kidneys. This paired organ is located in the retroperitoneal space, namely on the posterior surface of the abdominal cavity in the lumbar region on both sides of the spine. The right organ is anatomically located slightly lower than the left. Many of us believe that the only function of the kidneys is to produce and excrete urine. However, in addition to the excretory function, the kidneys have many other tasks. In our article, we will take a closer look at what the kidneys do.

Each kidney is surrounded by a sheath of connective and adipose tissue. Normally, the dimensions of the organ are as follows: width - no more than 60 mm, length - about 10-12 cm, thickness - no more than 4 cm. The weight of one kidney reaches 200 g, which is half a percent of the total weight of a person. In this case, the body consumes oxygen in the amount of 10% of the total oxygen demand of the body.

Despite the fact that normally there should be two kidneys, a person can live with one organ. Often, one or even three kidneys are present from birth. If, after the loss of one organ, the second copes with the double assigned load, then a person can fully exist, but he needs to beware of infections and heavy physical exertion.

Nephrons are responsible for the work of the kidneys - the main structural unit of the body. Each kidney has about a million nephrons. They are responsible for the production of urine. To understand what function the kidneys perform, it is necessary to understand the structure of the nephron. Each structural unit contains a body with a capillary glomerulus inside, surrounded by a capsule, which consists of two layers. The inner layer consists of epithelial cells, and the outer layer consists of tubules and a membrane.

Various functions of the human kidneys are realized due to the fact that nephrons are three types depending on the structure of their tubules and location:

Intracortical.
Surface.
Juxtamedullary.

The main artery is responsible for transporting blood to the organ, which inside the kidney is divided into arterioles, each of which brings blood to the renal glomerulus. There is also an arteriole that drains blood from the glomerulus. Its diameter is smaller than that of the adductor arteriole. Due to this, the necessary pressure is constantly maintained inside the glomerulus.

In the kidneys, there is always constant blood flow even against the background of increased pressure. A significant reduction in blood flow occurs with kidney disease, due to severe stress or severe blood loss.

The main function of the kidneys is the secretion of urine. This process is possible due to glomerular filtration, subsequent tubular secretion and reabsorption. The formation of urine in the kidneys occurs as follows:

First, blood plasma components and water are filtered through a three-layer glomerular filter. Formed plasma elements and proteins easily pass through this filtering layer. Filtration is carried out due to constant pressure in the capillaries inside the glomeruli.
Primary urine accumulates inside the collecting cups and tubules. Nutrients and fluids are absorbed from this physiological primary urine.
Next, tubular secretion is carried out, namely the procedure for cleaning the blood from unnecessary substances and transporting them into the urine.

Hormones have a certain effect on the excretory functions of the kidney, namely:

Adrenaline, produced by the adrenal glands, is needed to reduce urination.
Aldosterone is a special steroid hormone produced by the adrenal cortex. The lack of this hormone leads to dehydration, salt imbalance and a decrease in blood volume. An excess of the hormone aldosterone contributes to the retention of salt and fluid in the body. This in turn leads to edema, heart failure and hypertension.
Vasopressin is synthesized by the hypothalamus and is a peptide hormone that regulates fluid absorption in the kidneys. After drinking a large amount of water or when its content in the body is exceeded, the activity of the hypothalamus receptors decreases, which contributes to an increase in the volume of fluid excreted by the kidneys. With a lack of water in the body, the activity of receptors increases, which in turn leads to a decrease in urine secretion.

Important: against the background of damage to the hypothalamus, the patient has increased diuresis (up to 5 liters of urine per day).

Parahormone is produced thyroid gland and regulates the process of removing salts from the human body.
Estradiol is considered a female sex hormone that regulates the level of phosphorus and calcium salts in the body.

The following functions of the kidneys in the human body can be listed:

homeostatic;
excretory or excretory;
metabolic;
protective;
endocrine.

The excretory role of the kidneys is to filter the blood, cleanse it of metabolic products and remove them from the body. At the same time, the blood is cleared of creatinine, urea, and various toxins, such as ammonia. Various unnecessary organic compounds (amino acids and glucose), mineral salts that entered the body with food are also removed. The kidneys excrete excess fluid. The excretory function involves the processes of filtration, reabsorption, and renal secretion.

At the same time, 1500 liters of blood are filtered through the kidneys in one day. Moreover, approximately 175 liters of primary urine are immediately filtered. But since fluid absorption occurs, the amount of primary urine is reduced to 500 ml - 2 liters and is excreted through the urinary system. At the same time, urine is 95 percent liquid, and the remaining five percent is dry matter.

Attention: in violation of the excretory function of the body, the accumulation of toxic substances and metabolic products in the blood occurs, which leads to general intoxication of the body and subsequent problems.

Do not underestimate the importance of the kidneys in regulating the volume of intercellular fluid and blood in the human body. Also, this organ is involved in the regulation of ionic balance, removing excess ions and protons of bicarbonate from the blood plasma. It is able to maintain the required volume of fluid in our body by adjusting the ionic composition.

Paired organs are involved in the breakdown of peptides and amino acids, as well as in the metabolism of lipids, proteins, carbohydrates. It is in this organ that ordinary vitamin D is transformed into its active form, namely vitamin D3, which is necessary for the normal absorption of calcium. Also, the kidneys are an active participant in protein synthesis.

The kidneys are an active participant in the synthesis of the following substances and compounds necessary for the body:

renin is a substance that promotes the production of angiotensin 2, which has a vasoconstrictive effect and regulates blood pressure;
calcitriol is a special hormone that regulates calcium metabolism in the body;
erythropoietin is necessary for the formation of bone marrow cells;
prostaglandins are substances involved in the regulation of blood pressure.

As for the protective function of the body, it is associated with the removal of toxic substances from the body. These include certain drugs, ethyl alcohol, narcotic substances including nicotine.

negatively affects the functioning of the kidneys excess weight, hypertension, diabetes and some chronic diseases. For them, hormonal drugs and nephrotoxic drugs are harmful. The activity of the body may suffer due to a sedentary lifestyle, as this will contribute to the disruption of salt and water metabolism. It can also lead to the deposition of kidney stones. Causes of kidney failure include:

traumatic shock;
infectious diseases;
poisoning with poisons;
violation of the outflow of urine.

For the normal functioning of the body, it is useful to drink 2 liters of liquid per day. It is useful to drink berry fruit drinks, green tea, purified non-mineral water, parsley decoction, weak tea with lemon and honey. All these drinks are a good prevention of stone deposition. Also, to preserve the health of the body, it is better to give up salty foods, alcoholic and carbonated drinks, coffee.

The kidneys serve as a natural "filter" of the blood, which, when correct work remove harmful substances from the body. The regulation of kidney function in the body is vital for the stable functioning of the body and immune system. For a comfortable life, two organs are needed. There are times when a person stays with one of them - it is possible to live, but you will have to depend on hospitals all your life, and protection against infections will decrease several times. What are the kidneys responsible for, why are they needed in the human body? To do this, you should study their functions.

Let's delve a little into the anatomy: the excretory organs include the kidneys - this is a paired bean-shaped organ. They are located in the lumbar region, while the left kidney is higher. Such is nature: above the right kidney is the liver, which does not allow it to move anywhere. Regarding the size, the organs are almost the same, but note that the right one is slightly smaller.

What is their anatomy? Externally, the organ is covered with a protective shell, and inside it organizes a system capable of accumulating and removing fluid. In addition, the system includes parenchyma, which create the medulla and cortex and provide the outer and inner layers. Parenchyma - a set of basic elements that are limited to the connective base and shell. The accumulation system is represented by a small renal calyx, which forms a large one in the system. The connection of the latter forms a pelvis. In turn, the pelvis is connected to the bladder through the ureters.

Anatomical and physiological structure of the organ and its significance for the body

In their structure, the following structures are distinguished:

the glomerular apparatus (malpighian body), located in the thickness of the cortical substance, the main function of which is to filter the incoming blood;
a capsule that covers the outside of the glomerulus and acts as a "filter" through which the blood is cleansed of any kind of toxins and metabolic products;
a complex system of convoluted tubules that pass into each other and allow the reabsorption of the filtered fluid.

The tissues of each kidney contain at least 1 million actively functioning nephrons.

The work of all components of the nephron sequentially goes through three phases:

Plasma Filtration with the formation of primary urine (occurs in the glomeruli). During the day, approximately 200 liters of such urine is formed through the kidneys, which is close in composition to human plasma.
Reabsorption or reabsorption process necessary so that the body does not lose the necessary substances in the urine (this happens in the tubular system). Thus, vitamins, salts important to the body, glucose, amino acids and others are retained.
Secretion, in which all toxic products, unnecessary ions and other substances that are retained by the renal filter enter the final urinary sediment and are excreted irrevocably.

The work of the renal apparatus occurs in a constant mode, where one phase of the process smoothly replaces another

The adrenal glands consist of parenchyma and belong to a paired endocrine organ, which determines their main purpose in the human body. The oppression of their work leads to a number of serious disorders that require immediate medical intervention. Among the most common diseases that a specialist has to deal with, there is a pathology such as hypofunction of the adrenal glands (the production of certain hormones is sharply inhibited).

The adrenal glands are a vital organ for humans.

Functions of the kidneys and adrenal glands

The excretory (or excretory) activity of the kidneys includes the filtration and secretory functions, which were described above. Their main task is to remove toxins from the body through urinary sediment.

The final urine contains "unnecessary" waste products of the body

An equally important function of the kidneys is their ability to synthesize hormonal substances. The endocrine work of the body is associated with the entry into the blood of such hormones as:

renin (it is responsible for the balance of water in the body, prevents its excessive release and controls the constancy of blood volume in the circulatory bed);
erythropoietin (a substance that stimulates the production of red blood cells in bone marrow cells);
prostaglandins (control blood pressure).

The kidneys are able to maintain the balance of the ionic composition of the plasma and maintain a constant osmotic pressure in the body.

The most important functions of the adrenal glands are reflected in the following:

They are directly involved in many metabolic and metabolic processes.
They produce a number of vital hormonal substances that affect the functioning of individual body systems (mainly, these are the functions of the adrenal cortex).
Determine the behavior and reaction of the human body to stressful situations.
Thanks to the adrenal glands, the body's response to irritating external influences is formed.

The main function of the adrenal glands is the synthesis of hormonal substances.

Dysfunction

Main Factors

When it comes to etiological factors, that is, the causes that led to kidney disease, the following groups should be distinguished among them.

Prerenal mechanisms are caused by processes that indirectly affect the functional activity of the organ. These include:

various kinds of mental states, disorders in the work of the nervous system, as a result of which the development of reflex urinary retention is possible, up to its complete absence;
pathology of an endocrine nature, leading to a violation in the synthesis of hormonal substances that can affect the functioning of the kidney;
impaired blood supply to the organ during general hypotensive processes (for example, during collapse) or during a hypertensive crisis.

Renal mechanisms imply direct damage to the tissues of the kidney (inflammatory or autoimmune diseases, thrombosis, aneurysm or atherosclerosis of the renal vessels, and others).

Postrenal damage mechanisms are triggered when obstacles arise in the way of the natural outflow of urine (blockage of the lumen of the ureter by a stone, compression by a tumor process, and others).

The main types of acute renal failure

Development mechanisms

When exposed to any of the above factors, there are violations associated with a change in the processes of filtration, reabsorption or excretion.

Filtration changes can manifest themselves:

a decrease in the volume of filtered plasma in the glomerular apparatus (in hypotonic conditions, necrotic or sclerotic processes in the tissues of the glomeruli);
an increase in the volume of filtered plasma (hypertensive conditions, inflammatory processes leading to increased permeability of the glomerular membrane).

Changes in reabsorption are characterized by a slowdown in this process, which is most often associated with genetic abnormalities at the enzyme level.

Main manifestations

The work of the kidneys is evaluated according to the following characteristics:

Indicators of diuresis, that is, the amount of urine excreted during the day. Normally, a person excretes slightly less urine than he drinks liquids, and in case of pathology, the development of polyuria, oliguria or anuria is likely.
The density of the urinary sediment (normal ranges from 1008 to 1028). In pathology, they speak of hyperstenuria, hypostenuria or isosthenuria.
The components that make up urine and their quantitative ratio (we are talking about leukocytes, erythrocytes, protein, cylinders and others).

The functional work of the kidneys is assessed according to a number of diagnostic criteria for urinary sediment.

An acute process develops literally within a few hours, and its main sign is the progression and disorder of all vital processes.

Chronic insufficiency can develop for many years, this is due to the gradual death of nephrons.

Treatment

To restore the impaired functions of the renal apparatus, they resort to etiotropic and pathogenetic therapy, but do not forget about symptomatic treatment.

Etiotropic therapy includes the complete elimination or maximum correction of all causes that have become the source of the disease.

Conducting sessions of hemodialysis blood purification helps the human body fight the toxic effects of harmful substances and toxins

Symptomatic therapy includes a huge range of drugs that restore and correct the consequences of improper kidney function (hypotensive, diuretic drugs, and others).

Conclusion

Kidneys are vital organs of the human body. Thanks to them, the process of filtering the blood and removing metabolic products from the body takes place. To understand how great their role is, you need to study their structure and functionality.

The location of the kidneys in the body

Each of the pair of organs has bean shape. In the adult body, they are located in the lumbar region, surrounding the spinal column. In children - a little below the usual level. But, in the process of growth, the location of the kidneys returns to the desired level. To visually know their location, you just need to put your palms on your sides, and point your thumbs up. On the conditional line between the two fingertips and are the desired organs.

Their feature is the location in relation to each other. The right kidney is below the level of the left. The reason for this is that it is located under the liver, which does not allow the organ to rise higher. Sizes fluctuate 10 to 13 cm long and up to 6.8 cm wide.

The structure of the kidneys

Structural education is represented by the nephron. Man has them more than 800 thousand. Most of it is located in the cortex. Without nephrons, it would be impossible to imagine the process of formation of both primary and secondary urine, which is finally excreted from the body. One functional unit is represented by a whole complex, which includes:

Shumlyansky-Bowman capsule.
Kidney glomeruli.
tubular system.

Outside, the kidneys are surrounded by layers of adipose and connective tissue, the so-called "kidney pouch". It not only protects against damage, but also guarantees immobility. Organs are covered with parenchyma, consisting of two membranes. The outer shell is represented by a dark brown cortical substance, which is divided into small lobes, where are:

renal glomeruli. A complex of capillaries that form a kind of filter through which blood plasma passes into the Bowman's capsule.
Capsule of the renal glomerulus. Has a funnel shape. Filtered fluid passes through it, entering the renal pelvis.
tubular system. It is divided into proximal and distal sections. Fluid from the proximal canal enters the loop of Henle, and then into the distal part. It is in this complex that the reverse absorption of nutrients and vitamins into the bloodstream occurs.

The inner shell is represented by a light brown medulla, which includes pyramids (up to 12 units).

The blood supply to the kidneys is due to the system of arteries coming from the abdominal aorta. The filtered blood fluid enters the vena cava through the renal vein. It is important to note that in the organs themselves there is a huge number of blood vessels that feed the cell. Regulation of work occurs due to nerve fibers located in the parenchyma.

The main role of the kidneys

The main role of the kidneys in the body is to purify the blood by filtering it. It happens in the renal glomeruli. Then it enters the tubule complex, where it is reabsorbed. The secretion process begins in the pelvis and continues in the ureter. Surprising is the fact that more than 220 liters of blood are pumped through the kidneys daily, up to 175 liters of primary urine are formed. And this is an indicator of how important their continuous work is.

Organ functions

The following functions are assigned to the kidneys:

Metabolism. They are an important link in the synthesis of vital proteins, carbohydrates, and also form vitamin D3, which in its original form is produced in the subcutaneous layer when exposed to ultraviolet rays.
Urination. During the day, 170-175 liters of primary urine is formed in the human body, which, after thorough filtration and reabsorption, is excreted in the form of secondary urine with a volume of up to 1.9 liters. This is what helps cleanse the blood of excess fluid, salts, toxic substances such as ammonia, urea. But if this process is disrupted, then poisoning with harmful metabolites can occur.
Maintaining the constancy of indicators of the internal environment. There is a regulation of the level of blood and fluid in the body. The renal system does not allow the accumulation of excess water in the body, and also balances the concentration of mineral salts and substances.
Synthesis of hormones. Participate in the production of erythropoietin, renin, prostaglandin. Erythropoietin is the progenitor of blood cells originating in the red bone marrow. As a result of the action of renin, the level of circulating blood is regulated. And prostaglandin controls blood pressure.
Blood pressure control. This happens not only due to the production of the hormone, but also due to the removal of excess water.
Protection. Such harmful substances as alcohol, ammonia, toxic metabolites are removed from the body.
Stabilization of indicatorspH in blood plasma. This process is characterized by the removal of strong acids and the adjustment of the pH value. When deviating from a level equal to 7.44 units, infection may occur.

How important is the work of the kidneys in the body?

In the process of impaired functioning of the kidneys, the body undergoes poisoning, which causes uremia. This condition occurs with a large accumulation of toxic substances, accompanied by a violation of the water-salt balance. It is manifested by edema of the upper and lower extremities.

Health risks can bring urolithiasis disease , which is formed at the moment of high concentration of insoluble salts. To avoid this, you need to monitor the health of organs and use such types of annual diagnostics as urine and blood tests. It is advisable to conduct ultrasound diagnostics every 1.5 years.

Prevention of kidney disease

First, you should exclude the use of potent drugs and hormone-based drugs, pay attention to regular physical activity. To improve the functional activity of organs, it is necessary to consume at least 1.8 liters of water per day.

Herbal drinks are also useful, helping to cleanse the body of harmful metabolites. To avoid dehydration, it is advisable to minimize the amount of alcohol, carbonated and coffee drinks consumed and limit the amount of salt in the diet.

Many believe that the only function of the kidneys in the human body is to produce and excrete it.

In fact, these paired organs simultaneously perform several tasks, and with a pronounced disruption of the kidneys, serious pathological consequences can develop, which in a neglected form can lead to death.

Why are they needed and what functions do they perform in the body?

Endocrine. The production of erythropoietin, a hormone that is involved in the formation of blood cells in the bone marrow.

Ion-regulating or secretory. Maintaining the required level of acid-base balance in blood plasma.

This is necessary so that the blood does not develop pathogenic bacteria, for which an environment with an acid-base balance level above or below 7.4 units is favorable.

Also, the kidneys help maintain the level of water-salt balance in the blood, in case of violation of which there are malfunctions in the work of all vital systems of the body.

concentration. Regulation specific gravity urine.

Metabolic. Production of the active form of vitamin D-calcitriol. Such an element is necessary for the absorption of calcium in the intestine.

How do they work?

kidneys are supplied with blood through large vessels, suitable for organs from the sides. Also, through these vessels, fluids, toxic cleavage products various elements and other substances that must be removed from the body.

Through these vessels, which branch into small capillaries inside the kidneys, such fluids pass into the renal capsules, forming the primary urinary fluid. Further, such urine passes from the glomeruli formed by these capillaries to the pelvis.

Not all fluid that enters the kidneys is excreted: part of it is blood, which, after passing through the tissues of the kidneys, is cleansed and discharged through other capillaries into the renal vein, and from there into the general circulatory system.

The circulation of such fluids occurs constantly, and during the day both kidneys drive through themselves up to 170 liters of primary urine, and since it is impossible to remove such an amount, part of the liquid is reabsorbed.

During this process, all the beneficial components contained in it are filtered out as much as possible, which are combined with the blood before it leaves the kidneys.

If for some reason even a minor violation of such functions occurs - the following problems are possible:

increased blood pressure;
the risk of infection and subsequent inflammatory processes increases;
internal bleeding in the stomach and intestines;
decrease in the level of production of sex hormones;
development .

In case of serious acute violations of the functioning of the organs, the development of necrosis extending to the cortical layer is possible.

Progression is also possible, in which specific symptoms can be observed in the form of tremors of the limbs, convulsions, anemia. This increases the risk of stroke and heart attack, and in the worst case, death is possible.

How to check if there are violations?

Usually impaired renal function immediately noticeable by outward signs . These are swelling of the lower eyelids, urination disorders, general malaise. But sometimes such manifestations are absent, and it is possible to check the functionality of the kidneys only during the examination.

This diagnosis includes the following procedures:

. The results may show the presence of bodies, proteins, salts and compounds, the presence of which is characteristic of inflammation of the renal apparatus.
X-ray study. Allows you to visually assess the condition of the tissues of the kidneys. The procedure is performed using a contrast agent, which “highlights” the kidney tissue in the pictures.
. It is performed to assess the condition of the renal structures and can be carried out both for medical reasons and during the annual preventive examination. Also, the method allows you to track violations of the urinary tract.
If there are indications or suspicions of a violation of the functionality of the kidneys, procedures can be performed, computer and. Such studies allow us to examine specific parts of the organ with high accuracy and study it in different projections.

Restore and improve the functioning of the body

In case of violations of kidney function and, if necessary, to improve their work, no specific therapeutic methods are used.

On the human side, all that is required is follow certain recommendations:

Under these conditions, you can not worry about the normal functioning of the kidneys.

But even if a person leads a healthy lifestyle, it is necessary to be regularly examined by a specialist.

The origin of some kidney pathologies is still a mystery to specialists, and sometimes diseases occur without any prerequisites, and in the advanced stage, the treatment of such organs is always long and problematic, and often pathological processes are irreversible.

What do the kidneys do in the human body - see the video:

For the body is not limited to their excretory function.

Various options for the blood supply to the nephrons of the kidney ">

Various options for the blood supply to the nephrons of the kidney: a) juxtamedullary nephron; b) cortical nephron.

The non-excretory functions of the kidneys include, firstly, their participation in the metabolism of proteins and carbohydrates. Secondly, the kidneys, as the main organ for the production of erythropoietins, are involved in the processes of erythropoiesis. Thirdly, a number of biologically active substances are produced in the kidneys, for example, prostaglandins and renin, which determines the hormonal function of the kidneys. In addition, the kidneys perform different protective functions. The kidneys are also involved in the regulation of blood pressure. Finally, the kidneys are one of the main organs that guard the constants of the liquid internal environment of the body: pH, osmotic pressure, volume of the liquid internal environment of the body.

Thus, the kidney is an organ involved in ensuring the constancy of the main physicochemical constants of blood and other extra- and intracellular fluids of the body, circulatory homeostasis, regulation of the metabolism of various organic and inorganic substances.

At the core listed functions The kidneys are the processes occurring in its parenchyma: ultrafiltration in the glomeruli, reabsorption and secretion of substances in the tubules.

Features of blood circulation in the kidneys.
Under normal conditions, through both kidneys, which make up only about 0.43% of the body weight of a healthy person, passes from 1/4 to 1/5 of the volume of blood ejected by the heart. The blood flow in the renal cortex reaches 4-5 ml/min per 1 gram of tissue - this is the highest level of organ blood flow.

In the kidneys, a system of cortical and cerebral blood flow is isolated. Although the capacity of the vascular bed in them is approximately the same, about 94% of the blood flows through the system of cortical vessels and only 6% through the system of cerebral vessels. Cortical blood flow is closely related to the capillaries of the glomerulus. One of the main features distinguishing the cortical blood flow from the brain is that within a wide range of changes in blood pressure (from 90 to 190 mm Hg), the cortical blood flow of the kidney remains almost constant. This is due to a special system of self-regulation - autoregulation of cortical blood flow. Autoregulation of cortical blood flow ensures the constancy of the processes underlying urination in conditions of significant changes in extrarenal hemodynamics.

Nephron as a structural and functional unit of the kidneys.
Each human kidney contains about 1 million nephrons, which are its functional units. In the nephron, the main processes that determine the various functions of the kidneys occur. Each nephron includes a glomerulus with a capsule, a convoluted tubule of the first order, a loop of Henle, a convoluted tubule of the second order, and a collecting duct. In different departments of the nephron, different processes occur that determine the functions of the kidneys. This is also related to the location of the parts of the nephron. So the glomerulus and capsule, together with the convoluted tubules, are located in the cortical substance of the kidneys, while the loop of Henle and the collecting ducts go deep into their medulla.

Processes underlying urination.
In the glomeruli, the initial stage of urination occurs - filtration from the blood plasma into the capsule of the renal glomerulus of protein-free fluid - primary urine. The second stage is due to the fact that this liquid moves through the tubules, where water and substances dissolved in it are reabsorbed at different rates. The third process - tubular secretion - consists in the fact that the cells of the epithelium of the nephron capture a certain amount of a substance from the blood and intercellular fluid and transfer them to the lumen of the tubule.