Red blood cells without kernel. Blood cells
Some of these cells are never normal to leave the bloodstream, others are in the extension of their destination overlook other tissues of the body, which detects inflammation or damage.
Blood cells can be divided into red and white - erythrocytes and leukocytes. Erythrocytes All their lives - about 120 days - circulate on blood vessels and transfer oxygen and carbon dioxide. Erythrocytes constitute the bulk of blood cells. In the process of its ripening, they narrowly specialize to perform their most important function - the supply of body tissues with oxygen and removal of carbon dioxide.
To do this, they lose all "extra" cell elements, acquire a special concave shape, allowing them to penetrate into the smallest and curved capillaries, and fill their cytoplasm with hemoglobin molecules capable of reversible binding oxygen. For various diseases It may vary both form, size, amount of erythrocytes and hemoglobin levels. For the setting of the correct diagnosis, it is sometimes necessary to carry out additional tests, allowing to identify violations in the structure of the erythrocyte membrane or the presence of pathological forms of hemoglobin.
Leukocytes - White blood cells - struggle with infections and digest the remains of destroyed cellsleaving for this through the walls of small blood vessels in fabric. Leukocytes are divided into three main groups: granulocytes, monocytes and lymphocytes.
Monocytes, along with neutrophils, are the main "body sanitary panels", since their main function is the removal of fragments of old, narrowing, its cells, and foreign elements. For this, monocytes, leaving the bloodstream, become macrophages, which are much larger in size and longer live than neutrophils.
Lymphocytes are the main cells mediating the immune response. They are represented by two main classes:
- B-lymphocytes produce antibodies,
- T-lymphocytes kill cells, infected with virusand regulate the activity of other leukocytes.
In addition, there are lymphocytes - natural (natural) killers capable of killing tumor cells.
Platelets are contained in a large amount. In essence, they are not ordinary whole cells, but are small cell fragments separated from gigantic megacariocyte cells. Megacharocytes are not circulated in the blood, but are in the bone marrow, where "cellular plates" are separated from them - platelets. Platelets are capable of sticking to the inner surface of a damaged vessel, acting as an organizer of a patch, helping to restore the integrity of the vascular wall during blood coagulation.
The formation and ripening of most blood cells (hematopoedez) occurs in an adult in the bone marrow, where all the variety of blood cells are formed from a unique stem cell. The bone marrow is normal located in the large bones of a human skeleton, such as a femoral, pelvic bone, chest, and some others. However, lymphoid cells ripen outside the bone marrow - in the organs of the immune system, which are some areas of the intestinal mucosa, thymus, almond, spleen and Lymph nodes. The number of cells of each species is formed in strict accordance with the needs of the body, for which there is complex control. Therefore, changes in blood test formula have a huge diagnostic value. An experienced doctor, analyzing quantitative and high-quality shifts in the analysis of peripheral blood, is able to understand, among which pathological conditions should be carried out to a diagnostic search.
Contains many types of cells performing completely different functions - from oxygen transport until antibody generation. Some of these cells function exclusively within the circulatory system, while others use it only for transport, and their functions are performed in other places. However, the life cycle of all blood cells to some extent similar:
1) all lifetime is limited;
2) they are continuously formed and
3) they all go to the same type of bone marrow stem cells.
The blood is contained in the blood of erythrocyte nuclear-free cells - (4.0 - 5.0) x 1012 per liter, leukocytes - (4.0 - 6.0) x 109 per liter, among which grainy, or granulocytes are isolated, and energized, or agranulocytes (monocytes). Blood plates are also available in the blood (platelets), the number of which is (180.0 - 320.0) x 109 per liter. In the blood, the cells of the lymphoid series (lymphocytes) are constantly present, which are structural elements of the immune system.
Blood cells can be divided into red and white - erythrocytes and leukocytes. Erythrocytes remain within the blood vessels and carry oxygen and carbon dioxide associated with hemoglobin. Erythrocytes constitute the bulk of the cells circulating in the blood are tightly filled with hemoglobin and do not contain any conventional cellular organel, including even the kernel. Leukocytes are struggling with infection and digest the remnants of destroyed cells, etc., leaving for this through the walls of small blood vessels in the tissue.
In addition, the blood in large quantities contains platelets, which are not ordinary whole cells, and small cell fragments, or "mini cells", separated from the cortical cytoplasm of large cells, called megacariocytes. The platelets are specifically adhered to the endothelial fever of damaged blood vessels, where they help restore their wall during blood clotting.
Leukocytes are divided into three main groups: granulocytes, monocytes and lymphocytes.
Monocytes, leaving the bloodstream, become macrophages, which, along with neutrophils, are the main "professional
Blood - This is a viscous liquid of red, which flows by blood system: consists of a special substance - plasma carrying throughout the body different kinds Decorated blood elements and many other substances.
; Supply with oxygen and nutrients all organism.
; To transfer the products of metabolism and toxic substances to the organs responsible for their neutralization.
; Tolerate hormones produced endocrine glaresTo the tissues for which they are intended.
; Take part in the thermoregulation of the body.
; Interact with the immune system.
- Plasma blood. This is a liquid, by 90% consisting of water, carrying all the elements present in the blood, cardiovascular system: In addition to the fact that PPsma carries blood cells, it also supplies organs with nutrients, minerals, vitamins, hormones and other products involved in biological processes and takes the products of metabolism. Some of these substances themselves are freely transferred to PPasm, but many of them are insoluble and transferred only with the proteins to which they join, and are divided only in the relevant authority.
- Blood cells. Considering the composition of the blood, you will see three types of blood cells: the red blood tales, the color is the same as blood, the main elements that give it red; White blood tales responsible for many functions; and platelets, the smallest blood cells.
Red blood talesAlso called erythrocytes or red blood plates - rather large blood cells. They have a form of a two-way disc and a diameter of about 7.5 microns, in reality they are not cells as such, since they do not have a kernel; Erythrocytes live about 120 days. Erythrocytes contain hemoglobin - a pigment consisting of iron, thanks to which 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 product of metabolism - carbon dioxide - from the tissues to the lungs.
Red blood tales under a microscope.
If you put everything in a row red blood tales An adult, it will turn out more than two trillion cells (4.5 million per mm3 multiplied by 5 liters of blood), they can be 5.3 times placed around the equator.
White blood talesAlso called leukocytesPlay an important role in the immune system protecting the body from infections. Distinguish between several species of white blood taurus; All of them have a kernel, including some multi-core leukocytes, and are characterized by segmented bizarre cores, which are visible under the microscope, so leukocytes are separated into two groups: polyders and mononuclear.
Policide leukocytes Also called granulocytes, because under the microscope you can see several granules in which there are substances necessary to perform certain functions. There are three main types of granulocytes:
Let us dwell on each of the three types of granulocytes. Consider granulocytes and the descriptions of the description of which will follow further in the article in the Scheme 1 below.
Scheme 1. Blood cells: white and red blood tales, platelets.
Neutrophilic granulocytes (gr / n) - These are movable spherical cells with a diameter of 10-12 microns. The kernel is segmented, segments are connected by thin heterochromatic bridges. Women can see a small extended process, called the drum stick (Barra Taurus); It corresponds inactive long shouldch One of the two x chromosomes. On the concave surface of the nucleus there is a large complex of Golgi; Other organelles are weaker. Characteristic of this group of leukocytes is the presence of cell pellets. Azurophilic, or primary, granules (ag) are considered as primary lysosomes from the moment when they already contain acid phosphatase, aryulfatase, B-galactosidase, in-glucoronidase, 5-nucleotidase D-aminoxidase and peroxidase. Specific secondary, or neutrophilic, granules (NG) contain bactericidal substances lysozyme and phagocitin, as well as an enzyme - alkaline phosphatase. Neutrophilic granulocytes are microphages, i.e., absorb small particles, such as bacteria, viruses, small parts of the collapsing cells. These particles fall inside the body of the cell by capturing them with short cellularity, and then destroyed in phagelicosomes, inwards of which azurophilic and specific granules exempt their contents. The life cycle of neutrophilic granulocytes is about 8 days.
Eosinophilic granulocytes (GR / E) - Cells reaching 12 microns in diameter. The kernel is two-colon, the Golgjie complex is located near the concave surface of the nucleus. Cellular organelles are well developed. In addition to the azurophilic granules (AG), the cytoplasm includes eosinophilic granules (EG). They have an elliptic form and consist of fine-grained osmophilic matrixs and single or multiple dense lamellar crystalloids (CR). Lisosomal enzymes: lactoferrin and myeloperoxidase - concentrated in the matrix, while a large main protein, toxic for some helmintes, is located in crystalloids.
Basophilic granulocytes (GR / B) They have a diameter of about 10-12 microns. The kernel has a honestick or divided into two segments. Cellular organelles are poorly developed. The cytoplasm includes small rare peroxidazo-positive leases that correspond to the azurophilic granules (AG), and large basophilic granules (BG). The latter contain histamine, heparin and leukotrienes. Histamine is a vasodilatory factor, heparin acts as an anticoagulant (substance inhibiting the activity of the resulting blood system and preventing the formation of thrombus), and leukotrienes cause a narrowing of bronchi. Eosinophilic chemotactic factor is also available in granules, it stimulates the accumulation of eosinophilic granules in places allergic reactions. Under the influence of substances causing the liberation of histamine or IgE, in most allergic and inflammatory reactions may occur to degranulation of basophils. In this regard, some authors believe that basophilic granulocytes are identical to the fat cells of the connecting tissues, although the latter do not have peroxidazo-positive granules.
Severe two types monoyore leukocyte:
- Monocytes.which phagocytic bacteria, detritus and other harmful elements;
- Lymphocytesproducing antibodies (in-lymphocytes) and attacking aggressive substances (T-lymphocytes).
Monocytes (MC) - the largest of all uniform blood elements, about 17-20 microns. A large breast-like eccentric core with 2-3 nuclei is located in the bulk cytoplasm of the cell. The Golgi complex is localized near the concave nucleus surface. Cellular organelles are poorly developed. Azurophilic granules (AG), i.e. lysosomes, scattered inside the cytoplasm.
Monocytes are very movable cells with high phagocytic activity. Since the absorption of such large particles, as whole cells or large parts of broken cells, they are called macrophages. Monocytes regularly leave the bloodstream and penetrate into connect fabric. The surface of the monocytes can be like smooth and containing depending on the cell activity of pseudopodia, philodia, microville. Monocytes are involved in immunological reactions: participate in the processing of absorbed antigens, activation of T-lymphocytes, the synthesis of interleukin and the production of interferon. The life expectancy of monocytes is 60-90 days.
White blood tales, in addition to monocytes, exist in the form of two functionally different classes, called T- and in lymphocytesthat it is impossible to distinguish morphologically, based on ordinary histological methods Research. From a morphological point of view, young and mature lymphocytes distinguish. Large young V- and T-lymphocytes (CL) in size 10-12 μm contain, in addition to the round core, several cellular organelles, among which there are small azurophilic granules (AG) located in a relatively wide cytoplasmic rim. Large lymphocytes are considered as a class of so-called natural killers (killer cells).
Blood is the most important system in human organismperforming many different functions. Blood is a transport system, which is transferred to the authorities vital required substances and removed from cells spent substances, decay products and other elements that are subject to removal from the body. In the blood also occurs circulation of substances and cells, which ensure the protection of the body as a whole.
Blood consists of cells and a liquid part - serum consisting of proteins, fats, sugars and trace elements.
The composition of the blood is distinguished by three main types of cells:
- Erythrocytes;
- Leukocytes;
Erythrocytes - Cells transporting oxygen to tissues
Erythrocytes are called highly specialized cells that have no kernel (lost during maturation). Most of The cells are represented by two-screwed discs, the average diameter of which is 7 μm, and the peripheral thickness is 2-2.5 μm. There are also spherical and dome-shaped erythrocytes.
Due to the form, the cell surface is significantly increased for gas diffusion. Also, such a form contributes to an increase in the plasticity of the erythrocyte, so that it is deformed and moves freely on the capillars.
Pathological and old cells are very low, in connection with which they are delayed and destroyed in the spleen reticular tissue capillaries.
The erythrocyte membrane and cell-freeness of cells provide the main function of the erythrocytes - the transportation of oxygen and carbon dioxide. The membrane is absolutely impermeable for cations (except potassium) and high-permeable for anions. The membrane by 50% consists of proteins that determine the belonging of blood to the group and ensuring a negative charge.
Erythrocytes are different by:
- Size;
- Age;
- Sustainability of adverse factors.
Video: Erythrocytes
Erythrocytes - the most numerous human cells
Erythrocytes are classified according to the degree of maturity of groups having their distinctive features.
| stage of ripening | features |
|---|---|
| Eritroblast | diameter - 20-25 microns; core, which occupies more than 2/3 cells with nucleoli (up to 4); The cytoplasm is bright basophilic, purple color. |
| Proroamcite | diameter - 10-20 μm; core without nucleoli; chromatin coarse; The cytoplasm brightens. |
| Basophilic normoblast | diameter - 10-18 microns; chromatin segmented; The zones of baschromatin and oxychromatin are formed. |
| Polychromatophilic normoblast | diameter - 9-13 microns; destructive core changes; Oxyfly cytoplasm due to high hemoglobin content. |
| Oxyfly normoblast | diameter - 7-10 μm; Pink cytoplasm. |
| Reticulocyte | diameter - 9-12 microns; The cytoplasm is yellow-green. |
| Normocyte (mature red blood cell) | diameter - 7-8 microns; Red cytoplasm. |
Peripheral blood is found both mature and young and old cells. Young erythrocytes in which there are nuclei residues are called reticulocytes.
The number of young erythrocytes in the blood should not exceed 1% of the entire mass of red cells. An increase in the content of reticulocytes indicates enhanced erythropoes.
The process of formation of erythrocytes is called erythropoes.
Erythropoes occurs in:
- Bone marrow bones of the skull;
- Pelvis;
- Torso;
- Sternum and vertebral discs;
- Up to 30 years old, erythropoes also occurs in the shoulder and femoral bones.
Daily bone marrow forms more than 200 million new cells.
After complete ripening, the cells penetrate into the circulatory system through the capillary walls. The lifespan of erythrocytes ranges from 60 to 120 days. Less than 20% of the hemolysis of erythrocytes occurs inside the vessels, the rest are destroyed in the liver and spleen.
Erythrocyte functions
- Perform a transport function. In addition to oxygen and carbon dioxide, the cells transfer lipids, proteins and amino acids;
- Contribute to the removal of toxins from the body, as well as poisons that are formed as a result of metabolic and life processes of microorganisms;
- Actively participate in maintaining the balance of acid and alkali;
- Participate in the process of blood clotting.
The composition of the erythrocyte includes a complex iron-containing hemoglobin protein, the main function of which is the transfer of oxygen between the tissues and the lungs, as well as partial transportation of carbon dioxide.
The composition of hemoglobin includes:
- Large protein molecule - globin;
- Integrated non-chicken structure - GEMA. In the core of the hemy there is an iron ion.
In the lungs, iron is binding to oxygen, and it is this connection that contributes to the acquisition of the characteristic shade with blood.
Blood Groups and Rhow Factor
On the surface of the red blood cells there are antigens, which there are as far as species. That is why the blood of one person may differ from the blood of another. Antigens form a rhesus factor and group affiliation of blood.
| antigen | blood type |
|---|---|
| 0 | I. |
| 0a. | II. |
| 0b. | III |
| AB | IV |
The presence / absence on the surface of the erythrocyte antigen Rh determines the reserves factor (if there is RH, the reserves is positive, in the absence - negative).
The definition of the rhesus and group affiliation of human blood is of great importance when overflowing donor blood. Some antigens are incompatible with each other, causing the destruction of blood cells, which can lead to patient death. It is very important to overflow the blood from the donor, the blood type and the reserves of which coincide with the recipient indicators.
Leukocytes - blood cells performing phagocytosis
Leukocytes, or white blood tales, are called blood cells that perform a protective function. Leukocytes contain enzymes that destroy foreign proteins. Cells are able to detect malicious agents, "attack" them and destroy (phagocyant). In addition to the elimination of harmful microparticles, leukocytes take an active part in purifying blood from decay products and metabolism.
Thanks to antibodies that are produced by leukocytes, the human body becomes resistant to some diseases.
Leukocytes have a beneficial effect on:
- Metabolic processes;
- Providing organs and tissues with the necessary hormones;
- Enzymes and other necessary substances.
Leukocytes are divided into 2 groups: grainy (granulocytes) and non-refined (agranulocytes).
Common leukocytes include:
The group of endangelic leukocytes includes:
Veryukocyte varieties The largest leukocyte group is almost 70% of their total. Your name this species Leukocyte received due to the ability of the cell grain to be painted with paints having a neutral reaction.
Neutrophils are classified on the shape of the nucleus on:
- Youngnon-kernel;
- Caidiary, the kernel of which is represented by a stick;
- Segmentoreswhose core is the interconnected 4-5 segments.
When counting neutrophils in blood analysis, it is permissible for no more than 1% of young, no more than 5% of racial and no more than 70% of segmented cells.
The main function of neutrophilic leukocytes is protective, which is implemented due to phagocytosis, the process of detection, capture and destruction of bacteria or viruses.
1 Neutrophil is able to "neutralize" to 7 microbes.
Neutrophil also participates in the development of inflammation.
The smallest subspecies of leukocytes, the volume of which is less than 1% of the number of all cells. The basophilic leukocytes are named due to the ability of cell graininess to be painted only with alkaline dyes (Basic).
The functions of basophilic leukocytes are due to the presence of active biological substances in them. Basophiles produce heparin, which prevents blood clotting at the place of the inflammatory reaction and histamine, which expands the capillaries, which leads to a speedy resorption and healing. Basophiles also contribute to the development of allergic reactions.
The subspecies of leukocytes, which received its name due to the fact that its granules are painted with acid dyes, the main of which is Eosin.
The amount of eosinophils is 1-5% of the number of leukocytes.
Cells have the ability of phagocytosis, but their main function is to neutralize and eliminate protein toxins, foreign proteins.
Eosinophils are also involved in the self-regulation of the body systems, produce neutralized inflammatory mediators, participate in blood purification.
Eosinophil The subspecies of leukocytes, not having grain. Monocytes are large cells resembling a triangle forms. Monocytes have a large core of various forms.
The formation of the monocyte occurs in the bone marrow. In the process of ripening the cell passes several stages of ripening and division.
Immediately after the young monocyte matures, it goes into the circulatory system where 2-5 days live. After that, part of the cells die, and the part goes to "dive" to the stage of macrophages - the biggest blood cells whose life expectancy is up to 3 months.
Monocytes perform the following functions:
- Producing enzymes and molecules that contribute to the development of inflammation;
- Participate in phagocytosis;
- Contribute to tissue regeneration;
- Helps in the restoration of nerve fibers;
- Promotes the growth of bone tissues.
Macrophages phagocylate malicious agents that are in tissues and suppress the process of breeding pathogenic microorganisms.
The central link of the protection system, which is responsible for the formation of a specific immune response and provides protection against the entire foreign one in the body.
Education, ripening and division of cells occurs in the bone marrow, from where they are sent to the thymus, lymph nodes and a spleen for full ripening. Depending on where complete maturation occurs, T-lymphocytes are isolated (matured in thymus) and in-lymphocytes (matured in the spleen or in lymph nodes).
The main function of T-lymphocytes is the protection of the body, by participating the cells in immune reactions. T-lymphocytes phagocytic pathogenic agents, destroy viruses. The reaction that the data is carried out is the name "non-specific resistance".
B-lymphocytes are called cells capable of producing antibodies - special protein compounds that prevent the reproduction of antigens and neutralize the toxins allocated by them in the process of life. For each of the types of pathogenic microorganism, the in-lymphocytes produce individual antibodies, eliminating a specific appearance.
T-lymphocytes are phagocytic, mainly viruses, in-lymphocytes destroy bacteria.
What antibodies form lymphocytes?
B-lymphocytes produce antibodies that are contained in cell membranes and in the serum part of the blood. In the development of antibody infection, the antibodies begin to rapidly enter the bloodstream, where the pathogenic agents recognize and "inform" about it immune system.
The following types of antibodies are distinguished:
- Immunoglobulin M. - It is up to 10% of the total number of antibodies in the body. Are the largest antibodies and are formed immediately after the introduction of the antigen into the body;
- Immunoglobulin G. - The main group of antibodies, which plays a leading role in protecting the human body and forms immunity from the fetus. Cells are the most small among antibodies and are able to overcome the placental barrier. Together with this immunoglobulin, the fetus is transmitted immunity from many pathologies from his mother to her future child;
- Immunoglobulin A. - Protect the body from the influence of antigens entering the body from the external environment. The synthesis of immunoglobulin A is produced in lymphocytes, but large quantities are not contained in blood, but on mucous membranes, breast milk, saliva, tears, urine, bile and secrets of bronchi and stomach;
- Immunoglobulin E. - antibodies allocated in allergic reactions.
Lymphocytes and immunity
After moving the microbe with a in-lymphocyte, the latter is able to form in the "memory cells" in the body, which causes resistance to pathologies, whose pathogen is given to this bacterium. For the emergence of memory cells, medicine has developed vaccines aimed at forming immunity to particularly dangerous diseases.
Where are leukocytes collapsed?
The process of destruction of leukocytes is not fully studied. To date, it is proved that from all the mechanisms of cell destruction in the destruction of white blood cells, the spleen and lungs take part.
Platelets - Cells protecting the body from fatal blood loss
Platelets are shaped blood elements that are involved in providing hemostasis. Represented by small cells of the biconvecule form that do not have kernels. The platelet diameter varies within 2-10 μm.
Thrombocytes are produced with a red bone marrow, where 6 cycles of maturation pass, after which they go into the bloodstream and are located there from 5 to 12 days. The destruction of platelets occurs in the liver, spleen and bone marrow.
Being in the bloodstream, platelets have a disk form, but when the thrombocyte is activated, it acquires the form of a sphere on which pseudopodia is formed - special growths, with which platelets are combined with each other and stick to the damaged vessel surface.
In the human body, platelets perform 3 main functions:
- Create "traffic jams" on the surface of the damaged blood vessel, contributing to the cessation of bleeding (primary thrombus);
- Participate in blood clotting, which is also important for stopping bleeding;
- Platelets provide nutrition cells of vessels.
Platelets are classified on:
- Microform - platelet with a diameter of up to 1.5 microns;
- Normmoform - platelet with a diameter of 2 to 4 microns;
- Macroforms - platelet with a diameter of 5 microns;
- Megaloform - platelet diameter up to 6-10 microns.
The norm of erythrocytes, leukocytes and blood platelets (table)
| age | floor | erythrocytes (x 10 12 / l) | leukocytes (x 10 9 / l) | platelets (x 10 9 / l) |
|---|---|---|---|---|
| 1-3 months | husband | 3,5 - 5,1 | 6,0 - 17,5 | 180 - 490 |
| women | ||||
| 3-6 months | husband | 3,9 - 5,5 | ||
| women | ||||
| 6-12 months | husband | 4,0 - 5,3 | 180 - 400 | |
| women | ||||
| 1-3 years | husband | 3,7 - 5,0 | 6,0 - 17,0 | 160 - 390 |
| women | ||||
| 3-6 years old | husband | 5,5 - 17,5 | ||
| women | ||||
| 6-12 years old | husband | 4,5 - 14,0 | 160 - 380 | |
| women | ||||
| 12-15 years old |
Erythrocytes in humans and mammals are nuclear-free cells in the process of philo and ontogenesis of the core and most organelles. Erythrocytes are highly differentiated post-cell structures incapable of division.
The formation of erythrocytes (erythropoes) occurs in the red bone marrow. The duration of their life is 3-4 months, destruction (hemolysis) occurs in the liver and spleen. Before entering blood, the red blood cells consistently pass several stages of proliferation and differentiation in the erythron - red sprout of blood formation.
Typically, red blood cells have the shape of a two-way disc and contain in the main hemoglobin protein, which carries out gas binding.
The main function of the erythrocytes is respiratory - transportation of oxygen and carbon dioxide. In addition, red blood cells are involved in the transport of amino acids, antibodies, toxins and rows medicinal substances, adsorbing them on the surface of the plasmolem.
The normal number of erythrocytes: in men - (4.0-5.5) 10 12 / l, in women - (3.7-4.7) 10 12 / l.
The number of erythrocytes varies depending on the age and health status. The increase in the number of erythrocytes is most often due to oxygen starvation of tissues or pulmonary diseases, congenital defects hearts; It may occur during smoking, violation of erythropoese due to a tumor or cyst. A decrease in the number of erythrocytes is a direct indication of anemia (anemia). In the launched cases, under a number of anemia, the heterogeneity of erythrocytes largest and form, in particular iron deficiency anemia In pregnant women.
Sometimes in the gem, the trivalent iron atom instead of a divalent, and methemoglobin is formed, which is so firmly binds oxygen, which is not able to give it to tissues, resulting in oxygen starvation. Education of methemoglobin in red blood cells can be hereditary or acquired as a result of
actions on erythrocytes of strong oxidants, such as nitrates, some medications - Sulfanimides, local anesthetics (Lidocaine).
Leukocytes (White Blood Cells)
The source of leukocytes is a red bone marrow.
Leukocytes differ in structure and appointment. These cells have a kernel. Among them are distinguished granulocytes (neutrophilic, eosinophilic, basophilic), as well as lymphocytes and monocytes. Granulocytes contain granules that are painted with special dyes and visible under a microscope. Neutrophil granules are gray, eosinophils - orange, basophils - purple.
The main purpose of neutrophils is the protection of the body from infections. They phagocytic bacteria, that is, "swallow" and "digest" them. In addition, neutrophils can produce special antimicrobial substances.
Eosinophils remove excess histamine, which appears when allergic diseases. When infected with helminths, eosinophils penetrate the intestinal lumen, they are destroyed there, as a result, substances are released, toxic for helminths.
Basophiles, together with other leukocytes, are actively involved in inflammatory process, highlighting heparin, histamine, serotonin. The last two substances affect the vascular permeability and the tone of smooth muscles, sharply changing in the focus of inflammation. Heparin binds proteins that came out of cells into the intermediate substance, and weakens their adverse effect on cytoplasmic membranes.
Lymphocytes are the central link of the body's immune system. They carry out the formation of specific immunity, synthesis of protective antibodies, lysis of foreign cells, the reaction of the transplant rejection, provide immune memory. Differentiation of lymphocytes pass in the tissues. Lymphocytes, the ripening of which occurs in the forged gland, are called T-lymphocytes (thymus-dependent). There are several forms of T-lymphocytes. T-killers (killers) carry out the reactions of cellular immunity, lyinging alien cells, pathogens infectious diseases, Tumor cells, cells - mutants. T-helpers (helpers), interacting with B-lymphocytes, turn them into plasma cells, so on. Helive the flow of humoral immunity. T-suppressors (oppressors) block excessive reactions in lymphocygigs. There are also T-helpers and T-suppressors that regulate cellular immunity. Memory T cells store information about previously active antigens. B-lymphocytes (drier-dependent) are differentiating in humans in the lymphoid tissue of the intestines, the fabric of the sky and sip almonds. B-lymphocytes carry out the reactions of humoral immunity. Most in lymphocytes are antibodies. B-lymphocytes in response to the effect of antigens as a result of complex interactions with T-lymphocytes and monocytes are converted to plasma cells. Plasma cells produce antibodies that recognize and specifically bind the corresponding antigens. There are 5 main classes of antibodies, or immunoglobulins: JGA, JG G, JG M, JG D, JGE. Among B lymphocytes also distinguish killer cells, helpers, suppressors and cells of immunological memory. O-lymphocytes (zero) do not pass differentiation and are a reserve of T- and B-lymphocytes.
Monocytes are not enough mature cells. They begin to perform their basic functions when they turn into macrophages - large moving cells that are in almost all organs and tissues. Macrophages - peculiar seats. They "eat" bacteria, dead cells, and can "pull out" particles almost equal to them in size. Macrophages, as already mentioned, help lymphocytes in the implementation of immune reactions.
W. healthy man The number of leukocytes in the blood is inconvenient. After severe physical work, receiving a hot bath, in women during pregnancy, in the process of childbirth and before the start of menstruation it increases. It happens after meals. Therefore, that the results of the analysis be objective, it must be handed over to an empty stomach in the morning, not breakfast, you can drink only a glass of water.
An increase in the number of leukocytes is called leukocytosis, a decrease in leukopenia. The most common leukocytosis occurs in patients with infections (pneumonia, scarletin), purulent diseases (appendicitis, peritonitis, phlegmon), strong burns. Leukocytosis develops for 1-2 hours after the start of intensive bleeding. The attack of gout can also be accompanied by leukocytosis. For some leukemia, the number of leukocytes increases several tens of times.
Although the penetration of microbes into the human body usually stimulates the immune system, as a result of which the number of leukocytes in the blood increases, with some infections the opposite picture is noted. If the body's protective forces are exhausted and the immune system is not able to fight, the number of leukocytes is reduced. For example, leukopenia during sepsis testifies to the serious condition of the patient and unfavorable forecast. Some infections (abdominal typhoid, cortex, rubella, chickenpox, malaria, brucellosis, flu, viral
hepatitis) suppress the immune system, so they may be accompanied by leukopenia. The decrease in the number of leukocytes is also possible with a systemic red lupus, some leukemia and metastases of bone tumors.
Plates (blood plates)
Also formed from red bone marrow cells. There are flat cells of the irregular round shape with a diameter of 2-5 microns. Man platelets do not have nuclei, these are fragments of cells that are less than half of the erythrocyte. The number of blood platelets in human blood is (180-320) T0 9 / l. Daily fluctuations are occurring: thrombocyte during the night, than at night. The increase in platelets in peripheral blood is called thrombocytosis, reduction - thrombocytopenia.
The main function of platelets is to participate in hemostasis. Platelets help "repair" blood vessels, attaching to damaged walls, and also participate in blood clotting, which prevents bleeding and blood flow from the blood vessel.
The ability of platelets to adhere to a foreign surface (adhesion), as well as glued together (aggregation), under the influence of various reasons. Platelets produce and allocate a number of biologically active substances: serotonin (substance causing the narrowing of blood vessels, reduction of blood flow), adrenaline, norepinephrine, as well as substances that have received the name of the blood coagulation factors.