Violation of water-salt metabolism. Violations of the water-salt balance. Sodium deficiency in the body

Regulation of water excretion, osmoregulation

Water-salt metabolism is a set of processes of water and salts (electrolytes) entering the body, their absorption, distribution in internal environments and excretion. Daily consumption a person of water is about 2.5 liters, of which he receives about 1 liter from food. In the human body 2/3 total water falls on the intracellular fluid and 1/3 - on the extracellular. Part of the extracellular water is in the vascular bed (about 5% of body weight), while most of the extracellular water is outside the vascular bed, it is an interstitial (interstitial), or tissue, fluid (about 15% of body weight). In addition, a distinction is made between free water, water retained by colloids in the form of so-called swelling water, i.e. bound water, and constitutional (intramolecular) water, which is part of the molecules of proteins, fats and carbohydrates and is released during their oxidation. Different tissues are characterized by different proportions of free, bound and constitutional water. During the day, the kidneys excrete 1–1.4 liters of water, the intestines - about 0.2 liters; with sweat and evaporation through the skin, a person loses about 0.5 liters, with exhaled air - about 0.4 liters.

Water regulation systems salt metabolism ensure the maintenance of the total concentration of electrolytes (sodium, potassium, calcium, magnesium) and the ionic composition of the intracellular and extracellular fluid at the same level. In human blood plasma, the concentration of ions is maintained with a high degree of constancy and is (in mmol / l): sodium - 130-156, potassium - 3.4-5.3, calcium - 2.3-2.75 (including ionized, not bound to proteins - 1.13), magnesium - 0.7-1.2, chlorine - 97-108, bicarbonate ion - 27, sulfate ion - 1.0, inorganic phosphate - 1-2. Compared to blood plasma and interstitial fluid cells differ more high content potassium, magnesium, phosphate ions and a low concentration of sodium, calcium, chlorine and bicarbonate ions. Differences in salt composition blood plasma and tissue fluid are due to the low permeability of the capillary wall for proteins. Precise regulation of water-salt metabolism in a healthy person allows maintaining not only a constant composition, but also a constant volume of body fluids, maintaining almost the same concentration of osmotically active substances and acid-base balance.

The regulation of water-salt metabolism is carried out with the participation of several physiological systems. Signals coming from special inaccurate receptors that respond to changes in the concentration of osmotically active substances, ions and fluid volume are transmitted to the central nervous system, after which the excretion of water and salts from the body and their consumption by the body changes accordingly. So, with an increase in the concentration of electrolytes and a decrease in the volume of circulating fluid (hypovolemia), a feeling of thirst appears, and with an increase in the volume of circulating fluid (hypervolemia), it decreases. An increase in the volume of circulating fluid due to high content water in the blood (hydremia) can be compensatory, occurring after massive blood loss. Hydremia is one of the mechanisms for restoring the correspondence of the volume of circulating fluid to the capacity of the vascular bed. Pathological hydremia is a consequence of a violation of water-salt metabolism, for example, in renal failure, etc. A healthy person may develop short-term physiological hydremia after taking large amounts of liquid. The excretion of water and electrolyte ions by the kidneys is controlled by the nervous system and a number of hormones. Physiologically produced in the kidney also participate in the regulation of water-salt metabolism. active substances- derivatives of vitamin D3, renin, kinins, etc.

The content of sodium in the body is regulated mainly by the kidneys under the control of the central nervous system through specific natrioreceptors. responding to changes in the sodium content in body fluids, as well as volumoreceptors and osmoreceptors, responding to changes in the volume of circulating fluid and the osmotic pressure of the extracellular fluid, respectively. The sodium balance in the body is also controlled by the renin-angiotensin system, aldosterone, and natriuretic factors. With a decrease in the water content in the body and an increase in the osmotic pressure of the blood, the secretion of vasopressin increases ( antidiuretic hormone), which causes an increase reverse suction water in the renal tubules. An increase in sodium retention by the kidneys causes aldosterone, and an increase in sodium excretion causes natriuretic hormones, or natriuretic factors. These include atriopeptides that are synthesized in the atria and have a diuretic, natriuretic effect, as well as some prostaglandins, an ouabain-like substance formed in the brain, and others.

The main intracellular heap osmotically active cation and one of the most important potential-forming ions is potassium. Membrane resting potential, i.e. the potential difference between the cellular contents and the extracellular environment is recognized due to the ability of the cell to actively absorb K + ions from the external environment with energy expenditure in exchange for Na + ions (the so-called K +, Na + pump) and due to higher permeability cell membrane for K+ ions than for Na+ ions. Due to the high permeability of the inaccurate membrane for ions, K + gives small shifts in the potassium content in the cells (normally this is a constant value) and the blood plasma leads to a change in the membrane potential and excitability of the nervous and muscle tissue. The participation of potassium in maintaining acid-base balance in the body. An increase in the protein content in the cell is accompanied by an increased consumption of K+ ions by it. The regulation of potassium metabolism in the body is carried out by the central nervous system. with the participation of a number of hormones. Corticosteroids, in particular aldosterone, and insulin play an important role in potassium metabolism.

With a deficiency of potassium in the body, cells suffer, and then hypokalemia occurs. If renal function is impaired, hyperkalemia may develop, accompanied by severe disorder cell function and acid-base status. Often, hyperkalemia is combined with hypocalcemia, hypermagnesemia and hyperazotemia.

The state of water-salt metabolism largely determines the content of Cl - ions in the extracellular fluid. Chlorine ions are excreted from the body mainly with urine. The amount of excreted sodium chloride depends on the diet, active reabsorption of sodium, the state of the tubular apparatus of the kidneys, acid-base state, etc. The exchange of chlorides is closely related to the exchange of water: reduction of edema, resorption of transudate, repeated vomiting, increased sweating and others are accompanied by an increase in the excretion of chlorine ions from the body. Some saluretic diuretics inhibit sodium reabsorption in the renal tubules and cause a significant increase in urinary chloride excretion. Many diseases are accompanied by a loss of chlorine. If its concentration in the blood serum decreases sharply (with cholera, acute intestinal obstruction etc.), the prognosis of the disease worsens. Hyperchloremia is observed with excessive consumption table salt, acute glomerulonephritis, impaired patency urinary tract, chronic insufficiency blood circulation, hypothalamic-pituitary insufficiency, prolonged hyperventilation of the lungs, etc.

In a number of physiological and pathological conditions, it is often necessary to determine the volume of circulating fluid. For this purpose, special substances are injected into the blood (for example, Evans blue dye or labeled albumin). Knowing the amount of the substance introduced into the bloodstream, and after determining its concentration in the blood after a while, the volume of circulating fluid is calculated. The content of the extracellular fluid is determined using substances that do not penetrate into the cells. The total volume of water in the body is measured by the distribution of "heavy" water D2O, water labeled with tritium [pH] 2O (THO), or antipyrine. Water containing tritium or deuterium mixes evenly with all the water contained in the body. The volume of intracellular water is equal to the difference between the total volume of water and the volume of extracellular fluid.

The osmolality of blood plasma and extracellular fluid is mainly determined by sodium, since sodium is the main extracellular cation, and 85% of the effective osmotic pressure depends on sodium with accompanying anions. The remaining osmotically active substances account for approximately 15%, and the regulation of the osmolality of liquids internal environment actually comes down to maintaining a constant ratio of water and sodium. Water excretion by the kidney is regulated by neurohypophysis antidiuretic hormone (ADH) and is ultimately determined by those factors that affect the rate of ADH synthesis and secretion and its effect in the kidney.

The sensory mechanism of the antidiuretic system is represented by osmoreceptors with high sensitivity to the deviation of the osmolality of the blood plasma. After the discovery of osmosensitive elements in the hypothalamus by the English physiologist E. Verney, further progress in the study of the localization and function of central osmoreceptors was due to the development of electrophysiological studies and the radioimmune method for determining the concentration of ADH. In experiments on various animals, it was found that when a 2% sodium chloride solution is injected through a catheter into the carotid artery or directly into the brain through a microelectrode, the activity of individual neurons located in the zone of the third ventricle increases. Such neurons were located in the region of the supraoptic and paraventricular nuclei, that is, clusters of large cell neurons above the optic tract chiasm and near the wall of the third ventricle, in which ADH is synthesized, a stimulator of water reabsorption in the kidney. Osmoreceptors in the brain signal deviations from normal level osmolality of blood flowing to the brain.

The normal functioning of our body is an incredibly complex complex. internal processes. One of them is the maintenance of water-salt metabolism. When it is normal, we are in no hurry to feel our own health, as soon as violations occur, complex and quite noticeable deviations occur in the body. What is it and why is it so important to control it and keep it normal?

What is water-salt exchange?

Water-salt metabolism refers to the combined processes of the intake of liquid (water) and electrolytes (salts) into the body, the features of their assimilation by the body, distribution in internal organs, tissues, media, as well as the processes of their excretion from the body.

The fact that a person is half or more water is known to us from school textbooks. Interestingly, the amount of fluid in the human body varies and is determined by factors such as age, fat mass and the amount of the same electrolytes. If a newborn consists of water by 77%, then adult men - by 61%, and women - by 54%. So low quantity water in female body explained large quantity fat cells in their structure. By old age, the amount of water in the body decreases even below the indicated indicators.

The total amount of water in the human body is distributed as follows:

2/3 off total number discharged into the intracellular fluid; associated with potassium and phosphate, which are cation and anion, respectively;
1/3 of the total is extracellular fluid; a smaller part of it resides in the vascular bed, and a large part (over 90%) is contained in the vascular bed, and also represents interstitial or tissue fluid; sodium is considered to be a cation of extracellular water, and chlorides and bicarbonates are considered an anions.

In addition, water in the human body is in a free state, is retained by colloids (swelling water or bound water) or participates in the formation / breakdown of protein, fat and carbohydrate molecules (constitutional or intramolecular water). Different tissues are characterized by different proportions of free, bound and constitutional water.

Compared with blood plasma and intercellular fluid, tissue fluid in cells has a higher content of potassium, magnesium, phosphate ions and a low concentration of sodium, calcium, chlorine and bicarbonate ions. The difference is explained by the low permeability of the capillary wall for proteins. Precise regulation of water-salt metabolism in a healthy person allows maintaining not only a constant composition, but also a constant volume of body fluids, maintaining almost the same concentration of osmotically active substances and acid-base balance. .

Regulation water-salt metabolism organism occurs with the participation of several physiological systems. Special receptors respond to changes in the concentration of osmotically active substances, electrolytes, ions, and fluid volume. Such signals are transmitted to the central nervous system and only then there are changes in the consumption or excretion of water and salts.

The excretion of water, ions and electrolytes by the kidneys is controlled by the nervous system and a number of hormones. . In regulation water-salt metabolism physiologically active substances produced in the kidney are also involved - vitamin D derivatives, renin, kinins, etc.

The regulation of potassium metabolism in the body is carried out by the central nervous system with the participation of a number of hormones, corticosteroids, in particular aldosterone and insulin.

The regulation of chlorine metabolism depends on the work of the kidneys. Chlorine ions are excreted from the body mainly with urine. The amount of excreted sodium chloride depends on the diet, activity of sodium reabsorption, the state of the tubular apparatus of the kidneys, the acid-base state, etc. The exchange of chlorides is closely related to the exchange of water.

What is considered the norm of water-salt balance?

Lots of physiological processes in the body depends on the ratio of the amount of fluid and salts in it. It is known that a person should receive 30 ml of water per 1 kilogram of his weight per day. This amount will be enough to supply the body with minerals, spill along with them through the vessels, cells, tissues, joints of our body, as well as dissolve and wash out the waste products. On average, the amount of liquid consumed per day rarely exceeds 2.5 liters, such a volume can be formed approximately as follows:

from food - up to 1 liter,
by drinking plain water - 1.5 liters,
the formation of oxidation water (due to the oxidation of mainly fats) - 0.3-0.4 liters.

The internal exchange of fluid is determined by the balance between the amount of its intake and excretion for certain period time. If the body needs up to 2.5 liters of fluid per day, then approximately the same amount of it is excreted from the body:

through the kidneys - 1.5 liters,
by sweating - 0.6 liters,
exhaled with air - 0.4 liters,
excreted with feces - 0.1 liters.

Regulation water-salt metabolism is carried out by a complex of neuroendocrine reactions aimed at maintaining the stability of the volume and osmotic pressure of the extracellular sector and, most importantly, blood plasma. Although the mechanisms for correcting these parameters are autonomous, both of them are extremely important.

As a result of this regulation, a stable level of electrolyte and ion concentration is maintained in the composition of the intracellular and extracellular fluid. The body's main cations are sodium, potassium, calcium, and magnesium; anions - chlorine, bicarbonate, phosphate, sulfate. Their normal number in blood plasma is presented as follows:

sodium - 130-156 mmol / l,
potassium - 3.4-5.3 mmol / l,
calcium - 2.3-2.75 mmol / l,
magnesium - 0.7-1.2 mmol / l,
chlorine - 97-108 mmol / l,
bicarbonates - 27 mmol / l,
sulfates - 1.0 mmol / l,
phosphates - 1-2 mmol / l.

Violations of water-salt metabolism

Violations water-salt metabolism appear:

accumulation of fluid in the body or its deficiency,
edema formation,
a decrease or increase in the osmotic pressure of the blood,
electrolyte imbalance,
a decrease or increase in the concentration of individual ions,
change in acid-base balance (acidosis or alkalosis) .

The water balance in the body is completely determined by the intake and excretion of water from the body. Water metabolism disorders are closely related to electrolyte balance and are manifested by dehydration (dehydration) and hydration (an increase in the amount of water in the body), the extreme expression of which is edema:

edema- excess fluid content in the tissues of the body and serous cavities, in the intercellular spaces, usually accompanied by a violation of the electrolyte balance in the cells;
dehydration, being a lack of water in the body, is divided into:
- dehydration without an equivalent amount of cations, then thirst is felt, and water from the cells enters the interstitial space;
- dehydration with loss of sodium, comes from the extracellular fluid and thirst is usually not felt.

Violations water balance occur, and when the volume of circulating fluid decreases (hypovolemia) or increases (hypervolemia). The latter often happens due to hydremia, an increase in the water content in the blood.

Knowledge of pathological conditions in which the ionic composition of blood plasma or the concentration of individual ions in it changes is important for differential diagnosis various diseases.

Violations of sodium metabolism in the body are represented by its deficiency (hyponatremia), excess (hypernatremia) or changes in the distribution throughout the body. The latter, in turn, can occur with a normal or altered amount of sodium in the body.

sodium deficiency divided into:

true - associated with the loss of both sodium and water, which occurs with insufficient intake of salt, profuse sweating, with extensive burns, polyuria (for example, with chronic renal failure), intestinal obstruction and other processes;
relative - develops against the background of excessive administration aqueous solutions at a rate faster than the excretion of water by the kidneys.

Excess sodium distinguished in the same way:

true - takes place when administered to patients saline solutions, increased consumption of sodium chloride, delayed excretion of sodium by the kidneys, excessive production or prolonged administration of mineral and glucocorticoids from the outside;
relative - observed during dehydration and entails hyperhydration and the development of edema.

Disorders of potassium metabolism, 98% located in the intracellular and 2% in the extracellular fluid, are represented by hypo- and hyperkalemia.

hypokalemia observed with excessive production or introduction from the outside of aldosterone, glucocorticoids, causing excess secretion potassium in the kidneys, with intravenous administration of solutions, insufficient intake of potassium into the body with food. The same condition is likely with vomiting or diarrhea, since potassium is excreted with secrets. gastrointestinal tract. Against the background of such a pathology, dysfunction of the nervous system develops (drowsiness and fatigue, slurred speech), muscle tone decreases, motor skills weaken digestive tract, blood pressure and pulse.

Hyperkalemia turns out to be a consequence of starvation (when protein molecules break down), injuries, a decrease in the volume of circulating blood (with oligo- or anuria), excessive administration of potassium solutions. It reports itself with muscle weakness and hypotension, bradycardia up to cardiac arrest.

Violations in the ratio of magnesium in the body are dangerous, since the mineral activates many enzymatic processes, provides muscle contraction and passage nerve impulses by fibers.

Magnesium deficiency in the body occurs during starvation and a decrease in the absorption of magnesium, with fistulas, diarrhea, resection of the gastrointestinal tract, when magnesium leaves with the secrets of the gastrointestinal tract. Another circumstance is the excessive secretion of magnesium due to the intake of sodium lactate. In health, this condition is determined by weakness and apathy, often combined with a deficiency of potassium and calcium.

Excess magnesium It is considered a manifestation of its impaired secretion by the kidneys, increased cell decay in chronic renal failure, diabetes, hypothyroidism. There is a violation of a decrease blood pressure, drowsiness, depression respiratory function and tendon reflexes.

Calcium metabolism disorders are represented by hyper- and hypocalcemia:

hypercalcemia- a typical consequence of excessive intake of vitamin D in the body, probably due to increased secretion into the blood growth hormone, hormones of the adrenal cortex and thyroid gland in Itsenko-Cushing's disease, thyrotoxicosis;
hypocalcemia noted in kidney disease (chronic kidney failure, jade), while limiting the secretion of hormones into the blood parathyroid glands, decreased plasma albumin, diarrhea, vitamin D deficiency, rickets and spasmophilia.

Restoration of water-salt metabolism

Normalization water-salt metabolism is carried out with pharmaceutical preparations designed to correct the content of water, electrolytes and hydrogen ions (determining acid-base balance). These basic factors of homeostasis are maintained and regulated by the interconnected work of the respiratory, excretory and endocrine systems and in turn define the same job. Even minor changes in water or electrolyte content can lead to serious, life threatening consequences. Apply:

- is prescribed in addition to the main therapy for heart failure, myocardial infarction, cardiac arrhythmias (including arrhythmias caused by an overdose of cardiac glycosides), hypomagnesemia and hypokalemia; it is easily absorbed when taken orally, excreted by the kidneys, carries potassium and magnesium ions, promotes their penetration into the intracellular space, where it is actively involved in metabolic processes.
- prescribed for gastritis with hyperacidity, peptic ulcer stomach and duodenum, metabolic acidosis, which occurs with infections, intoxications, diabetes and in the postoperative period; the appointment is justified in case of stone formation in the kidneys, with inflammatory diseases top respiratory tract, oral cavity; quickly neutralizes hydrochloric acid gastric juice and has a rapid antacid effect, enhances the release of gastrin with secondary activation of secretion.
- is indicated for large losses of extracellular fluid or its insufficient intake (in case of toxic dyspepsia, cholera, diarrhea, indomitable vomiting, extensive burns) with hypochloremia and hyponatremia with dehydration, with intestinal obstruction, intoxication; It has a detoxifying and rehydrating effect, compensates for the lack of sodium in various pathological conditions.
- used to stabilize blood counts; binds calcium and inhibits hemocoagulation; increases the sodium content in the body, increases the alkaline reserves of the blood.
(ReoHES) - used in operations, acute blood loss, injuries, burns, infectious diseases as a prophylaxis of hypovolemia and shock; appropriate for violations of microcirculation; promotes the delivery and consumption of oxygen by organs and tissues, the restoration of capillary walls.

In the human and animal body, free water is distinguished, water is an intracellular and extracellular fluid that is a solvent of mineral and organic substances; bound water held by hydrophilic colloids as swelling water; constitutional water (intramolecular), which is part of the molecules of proteins, fats and carbohydrates and released during their oxidation. In different tissues, the ratio of constitutional, free and bound water is not the same.

In the process of evolution, very perfect physiological mechanisms regulation of water-salt metabolism, ensuring the constancy of the volume of fluids of the internal environment of the body, their osmotic and ionic indicators as the most stable constants of homeostasis.

In the exchange of water between the blood of capillaries and tissues, the proportion of the osmotic pressure of the blood (oncotic pressure), which is due to plasma proteins, is essential. This proportion is small and amounts to 0.03 - 0.04 stm of the total osmotic blood pressure (7.6 atm), however, due to the high hydrophilicity of proteins (especially albumins), oncotic pressure contributes to the retention of water in the blood and plays an important role in lymph and urination , as well as in the redistribution of ions between different water spaces of the body. A decrease in oncotic blood pressure can lead to edema.

There are two functionally related systems that regulate water-salt homeostasis - antidiuretic and antinatriuretic. The first is aimed at preserving water in the body, the second ensures the constancy of the sodium content. The efferent link of each of these systems is mainly the kidneys, while the afferent part includes osmoreceptors and volumoreceptors. vascular system, perceiving the volume of the circulating fluid.

With an increase in the osmotic pressure of the blood (due to loss of water or excessive intake of salt), excitation of osmoreceptors occurs, the release of antidiuretic hormone increases, and water reabsorption increases. renal tubules and decreased diuresis. At the same time, the nervous mechanisms that cause the appearance of thirst are excited. With excessive intake of water, the formation and release of antidiuretic hormone is sharply reduced, which leads to a decrease in the reabsorption of water in the kidneys.

The regulation of the release and reabsorption of water and sodium also largely depends on the total volume of circulating blood and the degree of excitation of volumoreceptors, the existence of which has been proven for the left and right atrium, for the pulmonary vein orifice and some arterial trunks. Impulses from volomoreceptors enter the brain, which causes the corresponding behavior of a person - he begins to either drink more water, or vice versa, the body will release more water through the kidneys, skin and other excretory systems.

The most important in the regulation of water-salt metabolism are extra-renal mechanisms, including the digestive and respiratory organs, the liver, spleen, as well as various departments central nervous system and endocrine glands.

The attention of researchers is attracted by the problem of the so-called salt choice: with an insufficient intake of certain elements into the body, a person begins to prefer food containing these missing elements, and vice versa, with an excessive intake of a certain element, a decrease in appetite for food containing it is noted. Apparently, in these cases important role plays specific receptors of internal organs.

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normal operation human body is an extremely complex set of many processes, one of which is water-salt metabolism. When he is in a normal state, a person is in no hurry to improve his own health, but as soon as really noticeable deviations arise, many immediately try to apply various measures. To prevent this from happening, it is best to figure out in advance what constitutes a water-salt exchange, and for what reason it is so important to maintain it in a normal state. Also in this article we will consider its main violations and ways to restore it.

What's this?

Water-salt metabolism is the intake of electrolytes and fluids in the body, combined with each other, as well as the main features of their assimilation and further distribution in the body. internal tissues, organs, environments, as well as all kinds of processes for removing them from the human body.

The fact that people themselves are more than half made up of water, every person has known since childhood, while the fact that the total amount of fluid in our body changes and is determined by a fairly large number of factors, including age, is quite interesting. total weight fat, as well as the number of those same electrolytes. If a newborn person consists of water by approximately 77%, then an adult man includes only 61%, and women - even 54%. So low maintenance water in the body of women is due to the fact that they have a slightly different water-salt metabolism, and there is also enough a large number of fat cells.

Key Features

The total amount of fluid in the human body is set approximately as follows:

Approximately 65% is allocated to the intracellular fluid, as well as associated with phosphate and potassium, which are an anions and cations, respectively.
Approximately 35% is extracellular fluid, which is mainly in the vascular bed and is tissue and interstitial fluid.

Among other things, it is worth noting the fact that water in the human body is in a free state, is constantly retained by colloids, or is directly involved in the formation and breakdown of protein, fat and carbohydrate molecules. Different tissues have a different ratio of bound, free and constitutional water, which also directly affects the regulation of water-salt metabolism.

In comparison with blood plasma, as well as a special intercellular fluid, tissue is distinguished by the presence of a sufficiently large amount of magnesium, potassium and phosphate ions, as well as a not so large concentration of calcium, sodium, chlorine and special bicarbonate ions. This difference is due to the fact that the capillary wall for proteins has a rather low permeability.

Correct regulation of water-salt metabolism in healthy people ensures not only the maintenance of a constant composition, but also the required volume of body fluids, maintaining the acid-base balance, as well as an almost identical concentration of the necessary osmotically active substances.

Regulation

It is necessary to correctly understand how the water-salt exchange works. The functions of regulation are carried out by several physiological systems. First, specialized receptors respond to all sorts of changes in the concentration of osmotically active substances, ions, electrolytes, as well as the volume of fluid present. In the future, signals are sent to the central nervous system of a person, and only then the body begins to change the consumption of water, as well as the release of it and the necessary salts, and, thus, the water-salt exchange systems regulate.

The excretion of ions, water and electrolytes by the kidneys is under the direct control of the nervous system and a number of hormones. In the process of regulation of water-salt metabolism, physiologically active substances produced in the kidney also take part. The total sodium content inside the body is constantly regulated mainly by the kidneys, which are under the control of the central nervous system, through specialized natrioreceptors that constantly respond to the occurrence of any changes in the sodium content inside the body fluids, as well as osmoreceptors and volume receptors that continuously analyze osmotic pressure extracellular, as well as the volume of circulating fluid.

The central nervous system is responsible for the regulation of potassium metabolism within the human body, which uses various hormones water-salt metabolism, as well as all kinds of corticosteroids, including insulin and aldosterone.

The regulation of chlorine metabolism directly depends on the quality of the kidneys, and its ions are excreted from the body in the vast majority of cases with urine. The total amount excreted directly depends on the diet used by the person, the activity of sodium reabsorption, acid-base balance, the state of the tubular apparatus of the kidneys, as well as the mass of other elements. The exchange of chlorides is directly related to the exchange of water, so the regulation of water-salt metabolism in the body affects many other factors. normal functioning various systems.

What is considered normal?

A huge number of different physiological processes occurring inside our body directly depend on the total amount of salts and liquids. On the this moment it is known that in order to prevent a violation of water-salt metabolism, a person needs to drink approximately 30 ml of water per kilogram per day own weight. This amount is enough to supply our body the right quantities minerals. In this case, the water will spill over various cells, vessels, tissues and joints, as well as dissolve and subsequently wash out all kinds of waste products. In the vast majority of cases, the average amount of water consumed during the day by a person practically does not exceed two and a half liters, and this volume is often formed something like this:

up to 1 liter we get from food;
up to 1.5 liters - by drinking plain water;
0.3-0.4 liters - the formation of oxidation water.

The regulation of water-salt metabolism in the body directly depends on the balance between the amount of its intake, as well as its excretion over a certain period of time. If during the day the body needs to get about 2.5 liters, then in this case, approximately the same amount will be excreted from the body.

Water-salt metabolism in the human body is regulated by a whole range of various neuroendocrine reactions, which are mainly aimed at constantly maintaining a stable volume, as well as the extracellular sector, and, most importantly, blood plasma. Despite the fact that the various mechanisms for correcting these parameters are autonomous, both of them are extremely important.

Due to this regulation, the maintenance of the most stable level of concentration of ions and electrolytes that are part of the extracellular and intracellular fluid is achieved. Among the main cations of the body, it is worth highlighting potassium, sodium, magnesium and calcium, while the anions are bicarbonate, chlorine, sulfate and phosphate.

Violations

It is impossible to say which gland is involved in water-salt metabolism, since in this process takes part huge amount a wide variety of organs. It is for this reason that in the process of the body's work a wide variety of violations can appear, indicating this problem, among which the following should be highlighted:

the occurrence of edema;
the accumulation of a large amount of fluid inside the body or, conversely, its deficiency;
electrolyte imbalance;
increase or decrease in osmotic blood pressure;
change ;
an increase or decrease in the concentration of some specific ions.

Specific examples

It must be correctly understood that many organs are involved in the regulation of water-salt metabolism, therefore, in the vast majority of cases, it is not immediately possible to establish the specific cause of the problem. Basically, the water balance is directly determined by how much water is entered and removed from our body, and any violations of this exchange are directly related to the electrolyte balance and begin to manifest themselves in the form of hydration and dehydration. The extreme expression of excess is edema, that is, too much fluid contained in various tissues of the body, intercellular spaces and serous cavities, which is accompanied by electrolyte imbalance.

When, in turn, is divided into two main types:

without an equivalent amount of cations, in which continuous thirst is felt, and the water contained in the cells enters the interstitial space;
with loss of sodium that comes directly from the extracellular fluid and is usually not accompanied by thirst.

All kinds of violations water balance are manifested when the total volume of circulating fluid decreases or increases. Its excessive increase is often manifested due to hydremia, that is, an increase in the total amount of water in the blood.

Sodium exchange

Knowledge of various pathological conditions in which changes occur in the ionic composition of blood plasma or the concentration of certain ions in it is important enough for differential diagnosis of a number of diseases. All kinds of disturbances in the exchange of sodium in the body are represented by its excess, lack or various changes in its distribution throughout the body. The latter occurs in the presence of a normal or altered amount of sodium.

Deficiency can be:

True. Occurs due to the loss of both water and sodium, which often manifests itself with insufficient intake of salt in the body, as well as too heavy sweating, polyuria, extensive burns, intestinal obstruction and many other processes.
Relative. It can develop against the background of excessive administration of aqueous solutions at a rate that exceeds the excretion of water by the kidneys.

Excess is also distinguished in a similar way:

True. It is the reason for the introduction of any saline solutions to the patient, too much consumption of ordinary table salt, all kinds of delays in the excretion of sodium by the kidneys, as well as excessive production or excessively prolonged administration of glucocorticoids.
Relative. Often observed in the presence of dehydration and is the direct cause of overhydration and further development all kinds of edema.

Recovery

It is possible to normalize the water-salt metabolism of the kidneys using specialized pharmaceuticals, which are developed specifically to change the total content of electrolytes, water and hydrogen ions. Support and regulation of the main factors of homeostasis is carried out due to the interconnected work of the excretory, endocrine and respiratory systems. Any, even the most insignificant changes in the content of water or electrolytes can lead to quite serious consequences some of which are even life-threatening.

What is assigned?

To normalize the water-salt metabolism of a person, you can use the following:

Magnesium and potassium asparangiate. In the vast majority of cases, it is prescribed exclusively as an addition to the main therapy in the event of heart failure, various violations heart rate or myocardial infarction. It is quite easily absorbed when taken orally, after which it is excreted by the kidneys.
sodium bicarbonate. It is mainly prescribed in the presence of peptic ulcer of the duodenum and stomach, as well as gastritis with high acidity, which occurs when intoxication, infections or diabetes occur, as well as during postoperative period. Neutralizes fairly quickly. hydrochloric acids gastric juice, and also provides an extremely fast antacid effect and increases general selection gastrin together with secondary activation of secretion.
Sodium chloride. It is taken in the presence of large losses of extracellular fluid or in the presence of its insufficient intake. Also, quite often, doctors recommend using it for hyponatremia, hypochloremia, intestinal obstruction and all kinds of intoxications. This tool has a rehydrating and detoxifying effect, and also provides restoration of sodium deficiency in the presence of various pathological conditions.
It is used to ensure the stabilization of blood counts. It is a binder for calcium, as well as an inhibitor of hemocoagulation. It further increases the total sodium content in the body and increases the alkaline reserves of the blood, which provides a positive effect.
Hydroxyethyl starch. It is used during operations, as well as for burns, injuries, acute blood loss and all kinds of infectious diseases.

Thus, you can normalize the water-salt metabolism and return the body to work. normal condition. Only a highly qualified doctor should choose a specific course of treatment, since you can significantly worsen the condition on your own.

With the approach of summer, many women, and even men, begin to dream about how they will slay everyone on the spot with their luxurious forms and muscular relief. But a mirror at the end of winter, alas, mercilessly makes it clear that in order to create a stunning figure, serious work is indispensable! Exercise stress, of course, one of the most important elements in this matter, but it is also important to put your metabolism in order. Let's talk about salt and water today!

Water-salt exchange

Amazing water...

How many adults remember what they were taught in school? If you carefully rummage through your memory, it turns out that there is not so much active knowledge gained in these "wonderful years". For example, E = mc2 (but who remembers the decryption?). Or that the human body is 65% water. Unfortunately, at school, we do not realize that all these boring laws, axioms, statements that you memorize without even trying to understand are quite applicable in life.

Well, take at least the same water. If children bothered to delve into the study of human anatomy and physiology, in particular, its metabolic processes, they could learn a lot of useful things even for this age. It would be useful for girls to know that water can be one of the reasons for weight gain. And the boys would probably be interested in reading about water poisoning. In general, since such necessary information did not come to us in childhood, we will correct the situation now.

Let's start, as usual, with the basics. But it is hardly worth repeating that thanks to water, life appeared on Earth and that without it a person will not last even a week. Let's skip this part. Let's jump right into the necessary explanation of why water is so important.

1. H2O is an essential element of most biochemical reactions.

2. Water performs a transport function, that is, it delivers the necessary substances to organs and tissues and removes end products of metabolism from the body.

3. It is a kind of gasket, weakening the friction between organs and tissues.

4. H2O is involved in thermoregulation.

More specifically, without enough water, the memory, and in principle the brain, will falter, the immune system can't withstand the pressure pathogenic bacteria, and it’s worth forgetting about a good mood.

Thirst is not hunger

Naturally, in order for the body to function normally, it needs a sufficient amount of H2O. It receives the main part of water from the consumed liquid, and also "pulls" it from food. This is on-duty information that everyone knows, but which should be supplemented. The fact is that a person daily loses more water than he receives. This happens due to simple chemical reaction: H2O molecules are formed during the oxidation of proteins (41 g of water per 100 g), fats (107 g of water per 100 g) and carbohydrates (55 g of water per 100 g).

About daily rate water consumption, there are different data. Basically, they are rather vague: from 1.5 to 3 liters. But there are also more specific figures. 40 g of H2O should fall on 1 kg of body weight. That is, suppose an adult weighing 60 kg should receive 2.4 liters of water per day (this amount includes the water contained in food). Unfortunately, modern people, especially those who have unlimited access to the "benefits" of civilization, often cannot understand what the body requires of them, and mistake the feeling of thirst for hunger.

Absorbing some bun instead of the treasured H2O, we break the water-salt balance. This is reflected in the metabolism, on which our weight directly depends. If there is not enough water, the breakdown of fats slows down, as the liver is forced to help the kidneys. This distribution of labor leads to the accumulation of stocks that do not paint the figure. There can be only one result and advice here: consume the right amount of water (you shouldn’t overdo it either) and lose weight before your eyes. By the way, experts recommend that you precede each meal with a glass of H2O, and after eating drink only an hour later. In this mode, water improves digestion, and does not interfere with it.

Dehydration

The most interesting part of almost any topic is deviations from the norm, so it's time to talk about dehydration and water poisoning.

Dehydration occurs with the loss of 10% of water, but if the body is deprived of 20% of H2O, death occurs. Easy degree dehydration is possible with overheating and heavy physical work. In addition, water leaves the body intensively during hyperventilation of the lungs and, of course, as a result of the action of certain diuretics. At insufficient consumption H2O concentration in the blood increases mineral salts, and this already leads to water retention in the body. The natural result is a disturbed metabolism.

The following signs indicate a lack of water: rapid pulse, shortness of breath, dizziness; if the losses are more significant, vision and hearing are impaired, speech problems arise, delirium appears, then irreversible disorders of the central nervous system, cardiac and respiratory systems occur. Surprisingly, even if you quench your thirst, dehydration can occur. The fact is that the body loses a lot of salt with sweat, so less H2O is required to get rid of the desire to drink, although in fact it may require much more.

And water poisoning

A mild degree of dehydration is somehow familiar to almost everyone, but water poisoning is a much more exotic thing. Yet our bodies are very clever. When excess water enters the body, the kidneys remove it, restoring the necessary balance. However, at certain conditions overhydration is also possible. It is manifested by nausea, aggravated after drinking water, increased moist mucous membranes. Also, patients suffer from drowsiness, headache, muscle twitching, convulsions, heart work is difficult, fat deposition is observed, and pulmonary edema may even develop. Get rid of poisoning intravenous administration sodium chloride solution (salt) and limiting water intake.

Potassium - to get rid of water

Water-salt metabolism is a process no less important for us than fat, protein or carbohydrate. Our mood and health directly depend on the intake of H2O and minerals. But if at the very least we still know something about water, then we have almost no idea about the macro- and microelements we need. So, let's get acquainted: macronutrients - calcium, potassium, magnesium, sodium, phosphorus, chlorine, sulfur; trace elements - iron, cobalt, zinc, fluorine, iodine, etc.

Most attention is usually paid to the concentration of potassium and sodium. It is on them that the water-salt balance depends. If there is more sodium in the body, H2O is retained. If there is more potassium, water, on the contrary, is actively excreted. In addition, K is involved in the transmission of nerve impulses, maintains the acid-base balance of the internal environment of the body, participates in the regulation of the activity of the heart, makes the rhythm of heart contractions rarer, and reduces the excitability of the heart muscle. Potassium is usually sufficiently present in food, so deficiency of this element is rare. There is a lack of K in drowsiness, lowering blood pressure, apathy, and cardiac arrhythmias. An excess of potassium is also expressed in drowsiness and a decrease in blood pressure, but confusion is also present, pain in the tongue, and flaccid muscle paralysis are characteristic. This element is found in parsley, celery, melon, potatoes, green onions, oranges, apples, dried fruits. An adult needs about 3 g of potassium per day.

Sodium - to store H2O

Sodium, like potassium, is involved in the transmission of nerve impulses and the regulation of acid-base balance, water-salt metabolism, but, in addition, it also increases the activity digestive enzymes. The need for this element in a temperate climate is 7-8 g of table salt per day. If NaCl is eaten more than necessary, water retention will occur, which will complicate the activity of the cardiovascular system and cause an increase in blood pressure. If sodium is less than normal, drowsiness, nausea, convulsions, dehydration appear, muscle weakness, dry mouth and many other unpleasant symptoms.

Magnesium - for peace of mind

Another very important element, about which it is impossible not to say - magnesium. It has a calming and vasodilating action. With a lack of magnesium in the diet, food absorption is disturbed, appetite worsens, growth is delayed, and calcium is deposited in the walls of blood vessels. In addition, there are very painful cramps. Magnesium is found in millet, oatmeal and buckwheat, beans, dried fruits, especially dried apricots. Every day a person needs about 0.5 g of this element.

False thirst

To complete the lecture, it is best to use some interesting fact. For example, this: thirst is true and false. True is caused by a decrease in the water content in the blood. Through vascular receptors, a signal about this is transmitted to the hypothalamus, and its excitation causes a desire to drink. With false thirst, the oral mucosa dries up. This effect occurs during reading, reports, lectures; at high external temperature; stressful situations. There is no physiological need to drink fluids at such moments.