RED BLOOD CELLS (ERYTHROCELLS)

The quantitatively predominant cellular form of normal blood of vertebrates is red blood cells- red blood cells. Usually their number in 1 mm 3 of blood is estimated in the millions, while the blood platelets of birds and lower vertebrates (thrombocytes) are estimated in the same volume of blood in the hundreds of thousands, and leukocytes in the thousands.

Therefore, on smears of physiologically normal blood, the main background consists of erythrocytes lying densely next to each other, stained with eosin in a bright pink or copper-red color.

Red blood cells perform an extremely important function in the body - transporting oxygen from the lungs to the tissues. This is achieved due to the content of iron-containing complex protein - hemoglobin - in red blood cells. Typically, erythrocytes contain 33% hemoglobin (corresponding to 12-17% hemoglobin in whole blood). Each gram of hemoglobin, turning into oxyhemoglobin, binds 1.34 cm 3 of oxygen, forming an easily dissociable chemical compound with it.

The collection of red blood cells from all the blood of an animal is called erythroid. In a horse weighing 500 kg, the erythron consists of 436.5 trillion red cells, with a total volume of 14.4 liters and contains 6.76 kg of hemoglobin. From a blood smear it is possible, with a certain skill, to form an approximate idea of ​​both the number of red blood cells based on the density of the cells on a uniformly obtained smear, and their saturation with hemoglobin - based on the color intensity (by the Romanovsky method) of each individual red blood cell. To count the number of red blood cells and to accurately determine the amount of hemoglobin, special blood testing methods are used. Detailed description These methods are given in any course of animal physiology. The picture of red blood with a special staining of the smear is especially valuable in that it makes it possible to recognize regenerative and degenerative changes in erythrocytes by different intensities of their staining with specific dyes, as well as by changes in the shape and internal structure of erythrocytes.

A. NORMOCYTES

The picture of red blood of a physiologically normal adult animal is characterized by an unconditional predominance of mature forms of red blood cells -- normotsigpov. Relatively very rarely, among the normocytes stained according to the Romanovsky method in a typical copper-red color, there are also immature erythrocytes - polychromatophils, stained in transitional colors from clear blue, typical for the juvenile form, through blue-violet , to a violet-red color, approaching the normal color of a mature red blood cell. There are no more than 1-5 such forms per 1,000 mature red blood cells in cows and horses and somewhat more in pigs, dogs, guinea pigs and rats.

The normocyte of mammals (with the exception of camels and llamas) is a round, nuclear-free, flat cell with thickened edges and a somewhat concave center. Actually, it would be more accurate to talk not about the cell, but about the rest of the cell, since the normocyte is deprived of the essential and most important component of the cell - the nucleus. (It is therefore better to use the name “red blood cell” for elements of the red blood of mammals than “erythrocyte”, although the latter is very widespread and has the advantage of brevity.)

In camels and llamas, normocytes are oval.

In profile, a normocyte has the appearance of a biscuit. It is better to imagine the shape of a normocyte as a plate or disk with thickened edges. According to some new data, red blood cells in circulating blood have a bell-shaped (“cap”) shape with a concave center. On an unstained smear, red blood cells appear yellow or greenish-yellow, corresponding to the color of hemoglobin in very thin layers. The peripheral part, as containing a thicker layer of hemoglobin, is colored more intensely.

With Giemsa stain, red blood cells are stained a beautiful pink-red, and with Pappenheim stain, they are copper-red. Since hemoglobin is selectively stained in this case, the color is more intense in the periphery, in the thickened part of the erythrocyte, where there is more hemoglobin. In the center the color is somewhat less intense, but normally quite noticeable. When hemoglobin formation is impaired, normocytes are stained atypically. Sometimes the color of only the central part of the red blood cell is sharply weakened. Then the red blood cell appears as a red ring with a lumen in the center - the so-called ring form. Such forms are especially typical even for physiologically normal dog blood.

In other cases, the amount of hemoglobin drops so much that the entire red blood cell (but, of course, primarily its center) is stained much weaker than normal. Such red blood cells are called hypochromic, and the phenomenon itself is called hypochromia.

Finally, there may be cases where red blood cells contain more hemoglobin than normal. Such red blood cells stain more intensely and are called hyperchromic (the phenomenon of hyperchromia).

When studying a smear with an additional count of the number of red blood cells and determining the amount of hemoglobin, it is possible to establish a very important indicator of the saturation of each individual red blood cell with hemoglobin - the so-called color index (indicator) of blood.

The color indicator cannot be determined, even very approximately, from a blood smear. It would seem that the intensity of the staining of red blood cells with eosin provides a basis for judging the saturation of erythrocytes with hemoglobin. However, this is far from the case. The color density of an erythrocyte depends, in addition to the intensity factor (hemoglobin concentration), also on the capacity factor (size of the erythrocyte, its thickness). In some anemias (especially microcytic hyperchromic anemia), the shape of the red blood cells changes dramatically. From flat, relatively stretched discs, they turn into thick bodies of much smaller diameter. At the same time, the color density of these seemingly smaller red blood cells increases significantly. In fact, the hemoglobin content in such red blood cells does not change or changes to a much lesser extent than it appears when examining them in stained smears.

The color index (U) does not indicate the absolute content of hemoglobin in one red blood cell, but a certain value proportional to the absolute content. The level of hemoglobin in the bloodstream is given in conventional percentages according to Sali. Normally colored

the indicator is equal to one (U = 1.0). A number greater than one indicates an excess of hemoglobin in the red blood cell (hyperchromia); a color indicator less than one indicates a reduced hemoglobin content (hypochromia).

The color index for farm and laboratory animals should be calculated using the following complete formula:

NRxHb

J= AHbxR

where: J - color index; NR-- normal for this species number of red blood cells in 1 mm 3 of blood; NHb-- normal for this type of animal. Many authors believe that in the vessels of animals, red blood cells have a cup-shaped or even bell-shaped shape (Gele, Weidenreich, Kryukov). Possible lifetime changes

the shapes of red blood cells are presented in the following diagram (Fig. 20).

Based on size, red blood cells can be divided into normocytes proper (for a horse - 5.6 µ in diameter), microcytes and macrocytes. Microcytes are red blood cells with a smaller diameter than normal (for a horse - less than 5 µ), macrocytes - larger (7-6 µ). The internal structure of erythrocytes is almost unclear, but the very presence of this intravital structure seems very probable. Otherwise, there would be an unstable shape of erythrocytes, “shadows of erythrocytes”, it is clear that they have elasticity, are in hemolysis, penetration of trypanoses into the erythrocyte without the release of hemoglobin from it, the undoubtedly proven presence of special, specifically stained formations in it, etc. On the surface, the red blood cell is delimited by a lipoid-protein membrane (Kryukov, Lepeshinskaya). To what extent is it differentiated histologically?

still controversial. The presence of a clearly defined erythrocyte membrane is defended by Nemilov and Lepeshinskaya.

Under the shell, the presence of “edge hoops” is assumed - elastic threads that form the skeleton of the erythrocyte (Fig. 21).

It is very likely that there are “internal bodies” in erythrocytes, as indicated by Maksimov, Arnold, and others.

A number of researchers (including N.D. Strazhesko) are developing an idea of ​​the very complex intravital structure of the so-called “perfect erythrocyte” of mammals. This largely hypothetical structure appears to consist of:

1. Nuclei, remnants of the nucleus or blood platelets (cr. p.).

2. Protoplasm, consisting of:

a) radial structure, only rarely visible (C);

b) basophilic substance piled up on top at a young age (polychromasia);

c) crusty complex outer shell(M).

3. Archoplasma, consisting of:

a) a lighter central substance (st. t.), corresponding to concavity (“vitreous body”);

b) microcenter (central body) with connection (c); in the microcenter there are two very small shiny grains;

c) adjacent, difficult to depict, 1-2 microns in size, spherical, the so-called “capsular body” (K).

It is unlikely, however, that such a complex structure can be considered sufficiently experimentally substantiated. Moreover, there are statements about the absence of such a complex structure in the erythrocyte (Nasonov). It is not entirely clear what physiological functions could be associated with such a complex and largely artificial structure of the red blood cell (Fig. 22).

The red blood cells of birds and lower vertebrates differ significantly from the red blood cells of mammals, primarily in that even in a mature state they contain nuclei. In addition, they are much larger in size and have an oval shape.

The loss of the nucleus by mature forms of mammalian erythrocytes probably occurred in the process of adaptation of these cells to oxygen transfer

Nuclear erythrocytes of birds and lower vertebrates are full-fledged cells with intense metabolism and therefore consume a significant amount of the oxygen they carry themselves. Mammalian erythrocytes, losing their nucleus, sharply reduce their gas exchange and, therefore, consume little of the oxygen they carry. Anucleate erythrocytes, therefore, are more “economical” oxygen carriers than karyocytes of birds and lower vertebrates.

In blood smears, red blood cells are sometimes seen closely superimposed on each other (“coin columns”). This ability is especially pronounced in the blood of a horse. It is very difficult to obtain a smear of horse blood where the red blood cells do not form a dense network overlapping each other. Individual red blood cells are usually found only on the thin, free edge of a horse's blood smear.

As the smear slowly dries, the concentration of blood plasma salts sharply increases, and in such a hypertonic solution, red blood cells, giving up water, take on an irregular star shape or the shape of mulberries.

The size of red blood cells varies significantly in different animal species, as does their number. Table 14 shows average data on the number and size of mature red blood cells in the main agricultural and laboratory animals. The general pattern is the inverse proportionality between the size and number of red blood cells in 1 mm 3 of blood.

According to V.P. Zaitsev, the size of a horse’s red blood cells depends on the type of constitution. Thus, in asthenic horses the average diameter of erythrocytes is 5.12 µ, in muscular horses it is 5.02 µ and in pyknic horses it is 4.9 µ.

In accordance with this, the number of erythrocytes, according to V.P. Zaitsev, depends on the constitution: 1 mm 3 of the blood of asthenic horses contains on average

9.97 million red blood cells, muscular 7.51 million and picnics 7.98 million.

Very little is known about the lifespan of red blood cells. Regarding anucleate red blood cells, there is evidence that their life cycle is 3-4 weeks. They undergo phagocytosis in the spleen, in the dilated capillaries of its pulp. The iron of their hemoglobin, together with part of the pyrrole rings of hematin, is deposited in the spleen in the form of an iron-containing pigment - hemosiderin. Part of the hemin that has lost iron enters the liver and is converted there into bile pigments. A certain amount of hemosiderin usually accumulates in the liver. This amount reaches enormous proportions in pathological conditions, when increased breakdown of red blood cells and hemoglobin occurs. The resulting iron-containing pigment intensively accumulates not only in the liver and spleen, but also in the bone marrow and lymphatic vessels, causing the phenomenon of hemosiderosis.

Hemosiderin should be considered as a reserve of iron and pyrrole rings, which can be used for the synthesis of hemoglobin.

When taking blood at general analysis quantitative indicators of erythrocytes and leukocytes are studied. Significant deviations from the norm will indicate some pathology. - This is red blood. These blood cells perform an important function in the human body. With their help, the tissues of the internal organs are saturated with oxygen and other necessary substances.

The erythrocyte contains iron. It is this protein that colors the red blood cell red, hence the name red blood. White blood consists of blood that has a bluish tint. If a blood test shows a low level of red blood cells, it means there are inflammatory processes in the body. The doctor prescribes therapy and also recommends changing a person’s diet and lifestyle.

Shows not only the quantitative indicators of red blood cells, but also the level of hemoglobin. To make a diagnosis, the color index, size, volume of red cells, as well as the average distribution of red blood cells will be required. Based on the overall picture, the doctor will be able to judge the state of health.

On every segment life path red blood cell standards are different:

• For women the figure is 3.4-5.1.
• For men, the norms are excellent and range from 4.1 to 5.7.
• The level of red blood cells in pregnant women is much lower and amounts to 3-3.5.
• Babies on their birthday have indicators from 5.5 to 7.2.
• Babies in the first year of life are 3-5.4.
• Children from 4-6.6 years old.

Small deviations from the norm, as a rule, can be easily corrected with the help of diet and taking the missing B vitamins. If significant deviations are observed, an inflammatory process occurs in the body. Your doctor may order additional tests to get a clearer picture of your health.

Do not forget that only a doctor can find the cause of a low red blood cell count.

Successful treatment of the patient depends on the correct diagnosis. Do not try to increase your red blood cell count on your own without consulting a specialist. This can lead to disastrous results.

If there are any deviations in test results, it is important to find their cause. You need to understand that it is not the blood cells themselves that are subject to therapy, but the disease that provokes a decrease in indicators.

Causes of low red blood cell levels

Deviations from the norm are provoked by a number of serious pathologies. Therefore, test results should be taken seriously and measures should be taken at the first signs of the disease.

One of the most common diseases, which results in a low level of red cells, is anemia and all its types. Low hemoglobin levels go hand in hand with low red blood cell counts.

Anemia is divided into several types:

• - this disease occurs due to blood loss, pregnancy or disruption of the absorption of iron from. This type of anemia is considered the most common.
• Sideroblastic anemia - this type of anemia does not imply a lack of iron, but of the enzyme by which synthesis occurs. This disease is not common, but is serious because it is incurable. A person takes a number of medications throughout his life to maintain his health.
• B12 deficiency and folic acid– vitamins B12 and B9 enter the body with food; they are not produced by themselves. The lack of these elements leads to anemia. More often it affects people who do not consume meat and fermented milk products, as well as pregnant women. Deficiency can occur due to gastrointestinal diseases; vitamins are not absorbed. The disease is treatable.
• Posthemorrhagic anemia - develops in response to large or small blood losses, chronic or acute. Chronic posthemorrhagic anemia occurs against the background of gastrointestinal diseases (ulcers, hernias), neoplasms, pathologies, etc. This type of anemia is dangerous because it cannot be detected immediately. Usually a person seeks help when he feels really bad.
• Hemolytic types of anemia - this disease involves the destruction of red blood cells, which occurs much faster than the generation of new blood cells to replace them. Such anemias are divided into those that are acquired or inherited.
• Sickle cell anemia - this anemia means an incorrect or defective form of the molecule, which leads to hemolytic crises - dizziness, shortness of breath, tinnitus, low blood pressure, fainting.
• Thalassemia is a hereditary disease due to which hemoglobin molecules are formed at a very low rate. The disease cannot be cured.
• Hypoplastic type - this disease differs from all others in that there is a deficiency of not only red blood cells, but also all other cells that make up the blood as a whole. The pathology is hereditary and acquired.

In addition to anemia, diseases such as erythroid leukemia can cause a low level of red cells. These are malignant tumors in the bone marrow, where the production of red blood cells occurs. Young cells undergo transition to malignant cells. Why this process occurs has not yet been established, but one of the factors identified is chemotherapy and radiotherapy procedures. Unless a person has been exposed to these factors, the reasons why cells in the bone marrow become malignant are not known.

You can learn more about anemia from the video:

The main cause of a low level of red blood cells is considered to be anemia and all its types. Therefore, the symptoms of such conditions are similar:

• With anemia, dizziness, headaches, low blood pressure, fainting, nausea, weakness, increased fatigue, insomnia, along with a drowsy state are observed.
• Diseases develop, enlargement of the liver and spleen in almost all cases.
• There may be problems with memory, loss of coordination, and conditions may develop about which a person says “woolly legs, arms,” or “goosebumps.”
• Problems with the cardiovascular system arise.

Depending on the type of anemia, the doctor prescribes appropriate treatment, recommends following a certain diet and following a regimen. The success of therapy depends on a correct diagnosis and strict adherence to all the doctor’s instructions.

Treatment for anemia usually requires taking medications to increase levels. Depending on the type of disease, either iron-containing or combination medications are prescribed.

In advanced cases, the patient is offered inpatient treatment, which will necessarily be accompanied by injections - iron-containing or combined solutions, B vitamins (12, 9).

The therapy will also include taking medications aimed at curing the main disease that provokes a decrease in red cells in the blood. For complex diseases, such as leukemia, treatment is carried out only inpatiently and may require a bone marrow transplant. The treatment regimen will always be different, as it depends on many factors that only a doctor can take into account.

Traditional recipes for increasing red blood cells

In folk medicine, there are a large number of recipes to combat. All of them, as a rule, contain basic plants that help cope with the disease.

These include wild strawberry leaves, rose hips, burnet (roots) and lungwort. It is recommended to make a mixture of these herbs and drink a small cup twice a day. You should not overdo it, as strawberry leaves, for example, reduce , which is already low in people suffering from anemia. Everything should be in moderation. The course of herbal treatment should be at least three months.

If it is not possible to drink herbal decoctions, prepare:

1. Beetroot juice with honey. To do this, boil the beets and squeeze the juice out of them, mix with honey to taste. Drink a tablespoon every day three times a day.
2. A mixture of dried fruits and honey. This medicine contains raisins, prunes, walnut, dried apricots and honey. Everything is mixed in equal proportions. Eat one or two teaspoons three times a day before meals.

This effective recipes from traditional medicine, which will certainly bring the content of hemoglobin and red blood cells back to normal. It is also recommended to drink juices from carrots, beets, raspberries, pomegranates and apples mixed with honey. However, it is worth remembering that juice therapy is an unsafe activity. Juices have a powerful effect and can cause deterioration in some diseases. Therefore, it is very important to consult a doctor before consuming any juices.

Usually the doctor himself recommends what diet to follow, what to drink and what juices will be beneficial.Of course, you need to make the juices yourself from fresh vegetables and fruits, rather than buying them at the store. Only in this case will a positive effect be observed.

A diet that includes vegetables, fruits, meat and dairy products is of no small importance.

It is very important to include beef liver and other offal in your diet. There should always be on the table:

• Red vegetables (beets, tomatoes), greens (cabbage, spinach).
• Fruits (apples)
• Meat, liver, kidneys ( beef is better and chicken, do not eat pork).
• Fermented milk products (cheese, cottage cheese, kefir).
• Chicken eggs.
• Cereals (buckwheat, lentils, oatmeal jelly or broth).

It is not recommended to eat fried or smoked foods, since anemia often causes disruptions in the gastrointestinal tract. Make it a rule to cook or stew everything. It is better to give up sweets - sweets, pastries, desserts. You can consume real dark chocolate in small quantities.

By following a diet and strictly following the instructions of doctors, anemia recedes, except for those types that cannot be cured. As a preventative measure, it is recommended to visit a therapist in a timely manner and take the test. Don't forget the lifestyle without bad habits, movement and balanced nutrition are the key to good health!

Blood- this is a viscous red liquid that flows through the circulatory system: it consists of a special substance - plasma, which is carried throughout the body various types formed blood elements and many other substances.

;Supply oxygen and nutrients the whole body.
;Transfer metabolic products and toxic substances to the authorities responsible for their neutralization.
;Transfer hormones produced by endocrine glands to the tissues for which they are intended.
;Take part in the thermoregulation of the body.
;Interact with the immune system.

- Blood plasma. It is a liquid consisting of 90% water that transports all the elements present in the blood throughout the cardiovascular system: in addition to transporting blood cells, it also supplies the organs with nutrients, minerals, vitamins, hormones and other products involved in biological processes, and carries away metabolic products. Some of these substances themselves are freely transported by the plasma, but many of them are insoluble and are transported only together with the proteins to which they are attached, and are separated only in the corresponding organ.

- Blood cells. When looking at the composition of blood, you will see three types of blood cells: red blood cells, the same color as blood, the main elements that give it its red color; white blood cells responsible for many functions; and platelets, the smallest blood cells.

Red blood cells, also called red blood cells or red blood plates, are fairly large blood cells. They are shaped like a biconcave disc and have a diameter of about 7.5 microns; they are not actually cells as such because they lack a nucleus; Red blood cells live for about 120 days. Red blood cells contain hemoglobin - a pigment consisting of iron, due to which the blood has a red color; It is hemoglobin that is responsible for the main function of blood - the transfer of oxygen from the lungs to the tissues and the metabolic product - carbon dioxide - from the tissues to the lungs.

Red blood cells under a microscope.

If you put everything in a row red blood cells For an adult human, there would be more than two trillion cells (4.5 million per mm3 times 5 liters of blood), which could be placed 5.3 times around the equator.

White blood cells, also called leukocytes, play important role in the immune system, which protects the body from infections. There are several types of white blood cells; All of them have a nucleus, including some multinucleated leukocytes, and are characterized by segmented, oddly shaped nuclei that are visible under the microscope, so leukocytes are divided into two groups: polynuclear and mononuclear.

Polynuclear leukocytes also called granulocytes, because under a microscope you can see several granules in them, which contain substances necessary to perform certain functions. There are three main types of granulocytes:

Let us dwell in more detail on each of the three types of granulocytes. You can consider granulocytes and cells, which will be described later in the article, in Scheme 1 below.

Scheme 1. Blood cells: white and red blood cells, platelets.

Neutrophil granulocytes (Gr/n)- these are mobile spherical cells with a diameter of 10-12 microns. The nucleus is segmented, the segments are connected by thin heterochromatic bridges. In women, a small, elongated appendage called the rod tympani (Barr's body) may be visible; it corresponds to the inactive long arm of one of the two X chromosomes. On the concave surface of the nucleus there is a large Golgi complex; other organelles are less developed. Characteristic of this group of leukocytes is the presence of cell granules. Azurophilic or primary granules (AG) are considered primary lysosomes from the moment they already contain acid phosphatase, aryle sulfatase, B-galactosidase, B-glucuronidase, 5-nucleotidase d-aminooxidase and peroxidase. Specific secondary, or neutrophil, granules (NG) contain the bactericidal substances lysozyme and phagocytin, as well as the enzyme alkaline phosphatase. Neutrophil granulocytes are microphages, i.e. they absorb small particles such as bacteria, viruses, and small parts of decaying cells. These particles enter the cell body by being captured by short cell processes and are then destroyed in phagolysosomes, into which azurophilic and specific granules release their contents. Life cycle neutrophil granulocytes for about 8 days.

Eosinophilic granulocytes (Gr/e)- cells reaching a diameter of 12 microns. The nucleus is bilobed; the Golgi complex is located near the concave surface of the nucleus. Cellular organelles are well developed. In addition to azurophilic granules (AG), the cytoplasm includes eosinophilic granules (EG). They have an elliptical shape and consist of a fine-grained osmiophilic matrix and single or multiple dense lamellar crystalloids (Cr). Lysosomal enzymes: lactoferrin and myeloperoxidase are concentrated in the matrix, while a large basic protein, toxic to some helminths, is located in the crystalloids.

Basophilic granulocytes (Gr/b) have a diameter of about 10-12 microns. The nucleus is kidney-shaped or divided into two segments. Cellular organelles are poorly developed. The cytoplasm includes small, sparse peroxidase-positive lysosomes, which correspond to azurophilic granules (AG), and large basophilic granules (BG). The latter contain histamine, heparin and leukotrienes. Histamine is a vasodilator, heparin acts as an anticoagulant (a substance that inhibits the activity of the blood coagulation system and prevents the formation of blood clots), and leukotrienes cause constriction of the bronchi. Eosinophilic chemotactic factor is also present in granules; it stimulates the accumulation of eosinophilic granules at sites of allergic reactions. Under the influence of substances that cause the release of histamine or IgE, basophil degranulation can occur in most allergic and inflammatory reactions. In this regard, some authors believe that basophilic granulocytes are identical to mast cells of connective tissues, although the latter do not have peroxidase-positive granules.

There are two types mononuclear leukocytes:
- Monocytes, which phagocytose bacteria, detritus and other harmful elements;
- Lymphocytes, producing antibodies (B-lymphocytes) and attacking aggressive substances (T-lymphocytes).

Monocytes (Mts)- the largest of all blood cells, measuring about 17-20 microns. A large kidney-shaped eccentric nucleus with 2-3 nucleoli is located in the voluminous cytoplasm of the cell. The Golgi complex is localized near the concave surface of the nucleus. Cellular organelles are poorly developed. Azurophilic granules (AG), i.e. lysosomes, are scattered throughout the cytoplasm.

Monocytes are very motile cells with high phagocytic activity. Since the absorption of large particles such as whole cells or large parts of broken cells, they are called macrophages. Monocytes regularly leave the bloodstream and enter the connective tissue. The surface of monocytes can be either smooth or contain, depending on the cellular activity, pseudopodia, filopodia, and microvilli. Monocytes are involved in immunological reactions: they participate in the processing of absorbed antigens, the activation of T lymphocytes, the synthesis of interleukin and the production of interferon. The lifespan of monocytes is 60-90 days.

White blood cells, in addition to monocytes, exist in the form of two functionally distinct classes called T- and B-lymphocytes, which cannot be distinguished morphologically, based on conventional histological methods of examination. From a morphological point of view, young and mature lymphocytes are distinguished. Large young B- and T-lymphocytes (CL), 10-12 µm in size, contain, in addition to a round nucleus, several cellular organelles, among which there are small azurophilic granules (AG), located in a relatively wide cytoplasmic rim. Large lymphocytes are considered a class of so-called natural killer cells.

(carbon dioxide) in the opposite direction.

However, in addition to participating in the breathing process, they also perform the following functions in the body:

• participate in the regulation of acid-base balance;
• maintain isotonicity of blood and tissues;
• adsorb amino acids and lipids from blood plasma and transfer them to tissues.

Formation of red blood cells

b) Then it turns red - now it is an erythroblast

c) decreases in size during development - now it is a normocyte

d) loses its nucleus - now it is a reticulocyte. In birds, reptiles, amphibians and fish, the nucleus simply loses activity, but retains the ability to reactivate. Simultaneously with the disappearance of the nucleus, as the erythrocyte matures, ribosomes and other components involved in protein synthesis disappear from its cytoplasm.

Reticulocytes enter the circulatory system and after a few hours become full-fledged red blood cells.

Structure and composition

Typically, red blood cells are shaped like a biconcave disc and contain primarily the respiratory pigment hemoglobin. In some animals (for example, camel, frog) red blood cells are oval in shape.

The contents of the red blood cell are represented mainly by the respiratory pigment hemoglobin, which causes the red color of the blood. However, in the early stages the amount of hemoglobin in them is small, and at the erythroblast stage the cell color is blue; later, the cell becomes gray and only when fully matured, it acquires a red color.

Human erythrocytes (red blood cells).

An important role in the erythrocyte is played by the cellular (plasma) membrane, which allows gases (oxygen, carbon dioxide), ions (,) and water to pass through. The plasmalemma is penetrated by transmembrane proteins - glycophorins, which, thanks to a large number sialic acid residues are responsible for approximately 60% of the negative charge on the surface of red blood cells.

On the surface of the lipoprotein membrane there are specific antigens of a glycoprotein nature - agglutinogens - factors of blood group systems (more than 15 blood group systems have been studied at the moment: AB0, Rh factor, Duffy, Kell, Kidd), causing agglutination of erythrocytes.

The efficiency of hemoglobin functioning depends on the size of the surface of contact of the erythrocyte with the environment. The total surface area of ​​all red blood cells in the body is greater, the smaller their size. In lower vertebrates, erythrocytes are large (for example, in the tailed amphibian Amphium - 70 microns in diameter), the erythrocytes of higher vertebrates are smaller (for example, in a goat - 4 microns in diameter). In humans, the diameter of an erythrocyte is 7.2-7.5 microns, thickness - 2 microns, volume - 88 microns³.

Blood transfusion

When blood is transfused from a donor to a recipient, agglutination (gluing) and hemolysis (destruction) of red blood cells are possible. To prevent this from happening, it is worth taking into account the blood groups discovered by K. Landsteiner and J. Jansky in 1900. Agglutination is caused by proteins located on the surface of the red blood cell - antigens (agglutinogens) and antibodies found in the plasma (agglutinins). There are 4 blood groups, each characterized by different antigens and antibodies. Transfusion is possible only between representatives of the same blood group. But for example, blood group I (0) is a universal donor, and IV (AB) is a universal recipient.

I - 0	II-A	III - B	IV - AB
αβ	β	α	--

Place in the body

The shape of the biconcave disc ensures the passage of red blood cells through the narrow lumens of the capillaries. In the capillaries they move at a speed of 2 centimeters per minute, which gives them time to transfer oxygen from hemoglobin to myoglobin. Myoglobin acts as a messenger, taking oxygen from hemoglobin in the blood and passing it on to cytochromes in muscle cells.

The number of red blood cells in the blood is normally maintained at a constant level (in humans there are 4.5-5 million red blood cells in 1 mm³ of blood, in some ungulates there are 15.4 million (llama) and 13 million (goat) red blood cells, in reptiles - from 500 thousand. up to 1.65 million, in cartilaginous fish - 90-130 thousand) The total number of red blood cells decreases with anemia, increases with polycythemia.

The lifespan of a human erythrocyte is on average 125 days (about 2.5 million erythrocytes are formed every second and the same number are destroyed). In dogs - 107 days, in rabbits and cats - 68.

Pathology

Human red blood cells various shapes(scheme).

Literature

• Yu.I Afansyev Histology, Cytology, and Embryology. / Shubikova E.A. - fifth revised and expanded. - Moscow: “Medicine”, 2002. - 744 p. - ISBN 5-225-04523-5

Wikimedia Foundation. 2010.

See what “Red Blood Cells” are in other dictionaries:

RED BLOOD CELLS, alternative common name for erythrocytes. Red blood cells. The figure shows a conventionally colored electron microphotograph of human red blood cells (cells), magnified 1090 times. They have the shape... ... Scientific and technical encyclopedic dictionary

RED BLOOD CELLS- RED BLOOD CELLS, see Erythrocytes...

Human see blood. In humans, red blood cells have an average diameter of about 7.7 thousandths of a mm. (from 4.5 to 9.7 according to Welker), in other mammals their diameter can be from 2.5 (musk deer) to 10; all mammals have K. blood... ...

red blood cells- honey erythrocytes, or red blood cells. The number of red blood cells should be from 3.8 to 5.8 million per 1 ml. If it is less than normal, it means there are not enough red blood cells, which indirectly indicates anemia. To confirm or deny... ... Universal additional practical explanatory dictionary I. Mostitsky

Leukocytes, lymphoid cells, lymphatic bodies, indifferent educational cells, also phagocytes, micro and macrophages (see below). This is the name given to those found in the blood next to red blood cells, as well as in many others... ... Encyclopedic Dictionary F. Brockhaus and I.A. Efron

HEMOLYSIS- HEMOLYSIS, HEMATOLYSIS (from the Greek haima blood and lysis dissolution), a phenomenon in which the stroma of erythrocytes, being damaged, releases Hb, diffusing into environment; in this case, the blood or a suspension of red blood cells becomes transparent (“varnish... ... Great Medical Encyclopedia

Elastic vibrations and waves with frequencies from approximately 1.5 2 ․104 Hz (15 20 kHz) and up to 109 Hz (1 GHz), the frequency range from 109 to 1012 13 Hz is usually called hypersound. The frequency range of the U. can be divided into three subregions: U. low ... ... Great Soviet Encyclopedia

The formation of blood in the vertebrate embryo occurs simultaneously with the formation blood vessels and from one rudiment common to them: vessels are formed in the form of continuous cords of mesodermic cells, of which the outer ones form the wall of the vessel, and ... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

- (lien, splen) the largest lymphatic gland, very constant in vertebrates and also found in some invertebrates. So, in a scorpion, a long cord stretches over the nerve cord in the abdomen, the cells of which have phagocytic... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

- (lien, splen) the largest lymphatic gland, very constant in vertebrates and also found in some invertebrates. So, in a scorpion, a long cord stretches over the nerve cord in the abdomen, the cells of which have phagocytic... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

Translated from Greek it sounds like “white blood cells”. They are also called white blood cells. They capture and neutralize bacteria, so main role Leukocytes are there to protect the body from disease.

Antonina Kamyshenkova / “Health-Info”

When your white blood cell count changes

Slight fluctuations in your white blood cell count are completely normal. But the blood reacts very sensitively to any negative processes in the body, and in a number of diseases the level of white blood cells changes dramatically. A low level (below 4000 per 1 ml) is called leukopenia, and it can be a consequence, for example, of poisoning with various poisons, radiation, a number of diseases (typhoid fever), and also develop in parallel with iron deficiency anemia. And an increase in white blood cells - leukocytosis - can also be a consequence of certain diseases, for example, dysentery.

If the number of white blood cells increases sharply (up to hundreds of thousands in 1 ml), then this means leukemia - acute leukemia. With this disease, the process of hematopoiesis in the body is disrupted, and many immature white blood cells are formed - blasts, which cannot fight microorganisms. It's deadly dangerous disease, and in the absence of its treatment the patient is at risk.