ERYTHROCYTES

From Big Medical Encyclopedia

ERITROTsYTY (erythrocytus, singular; Greek erythros red + kytos a receptacle, here — a cell) — the nuclear-free uniform elements of blood containing hemoglobin.

About existence E. it became known more than 300 years ago when in 1658 J. Swammerdam found «red balls» in blood of a frog. Then A. Levenguk in 1673 found them in blood of the person. Major functional importance E. it was found out in the second half of 19 century. Not the small merit in it belongs to I. M. Sechenov.

Quantity circulating E. in an organism of the healthy adult in usual conditions makes 25*1012 — 30» 1012. Normal average indicators of maintenance of erythrocytes in 1 mkl blood it is considered to be for men 4,0 — 5,0 million, for women — 3,9 — 4,7 million. Education E. is a final stage of an erythrocytopoiesis (see the Hemopoiesis, Marrow). Marrow produces within 1 hour about 1010 erythrocytes, and in days (at the rate on 1 kg of weight) at men 3,5 * 109, at women 2,63 * 109 erythrocytes. With loss of a kernel the erythroidal cell turns in a re-tic lotsit; it contains basphilic substance (reticulum), edges well comes to light at supravital coloring by brilliantkrezilo-vy blue and the ribosome of lny complexes, mitochondrions and other organellas represents the remains. During the coloring of blood or marrow — to Gimza (see Romanovsky — Gimza a method) reticulocytes are determined by Romanovsky as on-likhromatofily (see the Polychromatophilia). In size they are slightly larger mature E. At scanning electron microscopy (see) on a surface of reticulocytes small deepenings are visible (fig. i, a). Blood of the adult healthy person contains usually 0,2 — 1% of reticulocytes (see Gemogramm, Blood). Their quantity reflects a functional condition of marrow. The reticulocytopenia (decrease in maintenance of reticulocytes in blood) demonstrates oppression of an erythrocytopoiesis that is noted, e.g., at the inborn and acquired hypoplastic and aplastic anemias (see. Hypoplastic anemia). The reticulocytosis (the increased maintenance of reticulocytes) indicates the vigorous activity of a sprout of red marrow connected, e.g., with acute blood loss or hemolitic crisis (see Crises). At patol. states can come to blood unripe on-likhromatofilnye erythrocytes or erythrocytes with basphilic stippling. The last differ from reticulocytes in character of an arrangement of inclusions and their ability to be painted gematoksili-


by Fig. 1. Various forms of erythrocytes of blood revealed at scanning electron microscopy: and — reticulocytes (are specified by shooters); x 4000; — a stomatocyte (above) and a planocyte (below); x 5000; in — sferotsit with proteinaceous imposings;

X 5000; — a mikrosferula; X 5000.


Fig. 2. Transformation of a diskotsit (D) in sferotsit (Federation Council): through a stage of ekhinotsit of 1 — 4 orders (9xt, Ekh2, Ekh3, Ekh4) and through a stage

of stomatocytes of 1 — 4 orders (Sti of St2, St3, St4).

number and other basphilic dyes.

Structure, form, sizes and function of erythrocytes. At a research E. by means of a transmission supermicroscope the high homogeneous electron-optical density of cytoplasm at the expense of the hemoglobin which is contained in it is noted (see); organellas are absent. Plasmolemma (cellular membrane) E. has complex structure and consists of four layers. The periblast is formed by glycoproteins and contains branched complexes of oligosaccharides, to-rye represent trailer departments of group antigens of blood (see Blood groups). The adsorbed proteins of plasma partially enter the same layer. Average two layers form the classical double lipidic membrane (see Membranes biological) including globular proteins. The main part of lipids consists of phospholipids, cholesterol and glycerides. The internal, turned to cytoplasm layer consists of proteins — spectrin and actin. Spectrin has sokratitelny ability and K+, KA + - dependent ATF-aznoy activity, molecules of glycolytic enzymes and hemoglobin are connected with it. Rheological properties E., plasticity of their plasmolemma in many respects are defined by a structurally functional condition of this protein. From other structural proteins E. were allocated and identified glikofo-rin and sialoglikoprotein.

At scanning electron microscopy erythrocytes of various form come to light (see fig. 1 and 2 to St. Blood, t. 12, Art. 96). Among circulating E. ground mass is made by diskotsita; also spherical shapes — an ostomy - totsita, ekhinotsita, sferotsita meet. Dis-kotsit represents a biconcave disk with a plain surface. The area of its surface approximately by 1,7 times exceeds surface area spherical E. at the equal volume of cells. Consider that E. in the form of a disk are most adapted to diffusion of gases and transport of various substances through a plasmolemma; vast majority E. easily passes on the capillaries having twice the smaller diameter, than a cell. These properties E. are caused by their high ability to change the configuration at the expense of a diskopodobny form of a cell, rather light body of normal hemoglobin and elasticity of a cellular membrane. Spherical shapes E. have the lowered elasticity, in this regard they are late in a filtrational bed of a spleen and are destroyed by macrophages.

Ekhinotsit it is formed of a diskotsit; at the same time at first on a circle of a diskotsit, and then on all surface of a cell there are rough outgrowths (at this stage diskotsit has an appearance of a hedgehog or mulberry berry) then it gains spherical shape (fig. 2). Transformation of a diskotsit in ekhinotsit is reversible until there are losses of a part of outgrowths of a plasmolemma. A final stage of such transformation is education sferotsi-that. Formation of ekhinotsit causes a number of factors as intracellular (decrease in concentration of ATP, accumulation of calcium ions and lysolecithin in E.), and extracellular (change of electrolytic structure of a blood plasma, pH, temperature, concentration fat and bilious to - t, and also influence of nek-ry pharmaceuticals, in particular salicylates and barbiturates). Normal the quantity of ekhinotsit does not exceed 1%. At long-term storage of stored donor blood the quantity of ekhinotsit increases up to 70 — 80% as a result of loss by erythrocytes of ATP.

The stomatocyte develops from a diskotsit as a result of metabolic disturbances in a cell. Transformation begins with smoothing of a contour of a diskotsit on the one hand; AA. becomes dome-shaped, then a concave part of a cell decreases, and AA. takes spherical shape (fig. 2). This process is reversible to a stage of loss of sites of a plasmolemma. In normal conditions stomatocytes make 2 — 5% of erythrocytes.

A spherocytosis — increase in amount of spherical shapes E. in blood — demonstrates about patol. the deviations in an organism determined by the hereditary or acquired disturbing factors. For identification of the raised sferulyation of erythrocytes define a spherocytic index, or an indicator of sphericity (see Eritro-tsitometriya). At irreversible transformation of a diskotsit in sferotsit outgrowths of a plasmolemma turn into miyelinopodobny figures or any a microsphere-ly (fig. 1, d).

Depending on a form E. allocate also planocytes (fig. 1,6) — thin diskotsita with wide, but


Fig. 3. Targetoid erythrocytes at a thalassemia in a svetooptichesky microscope; X 1500.

rather small deepening, characteristic of an iron deficiency anemia (see); drepanocytes — crescent E., revealed at a sickemia (see); targetoid erythrocytes (fig. 3) — diskotsita with it is central the located eminence, the most often meeting at a thalassemia (see); dipsotherapies (elliptotsit)

— the diskotsita of an oval or ellipsoidal form characteristic of ovalotsitarny hemolitic anemia (see). At anemias E. can get various bizzare shapes, this phenomenon received the name «poikilocytosis».

Sizes E. the person are quite changeable. In the dried-up blood smears of the healthy person the absolute majority of erythrocytes is presented by normocytes. Their average diameter is equal to 7,2 — 7,5 microns, the average thickness of 1,9 — 2,1 microns, average volume 76 — 96 mkm3, surface area 140 — 145 mkm2. By data I. A. Kassirsky and

G. A. Alekseev (1970), the microcyte has diameter less than 6,7 microns, diameter of a macrocyte is more than 7,7 microns, diameter of a megaloyte exceeds 9,5 microns. Sometimes meet E. (schizocytes) with a diameter of 2 — 3 microns. At healthy adults the quantity of normocytes averages 70% that defines degree fiziol. anisocytosis, i.e. distinction E. in size. Reduction of number of normocytes at increase in number of microcytes (microcythemia) and (or) macrocytes (macrocytosis) is one of precursory symptoms of disturbance of an erythrocytopoiesis. At anemias it becomes the most expressed. The microcythemia is characteristic of iron deficiency states and mik-rosferotsitarny hemolitic anemia (see. Hemolitic anemia). The shift towards a macrocytosis is most often connected with the lack of an organism of antianemic factors strengthened by an erythrocytopoiesis or disturbance of functions of a liver. The most exact idea of distribution E. in size the erythrocytometric curve, or a so-called Price-Jones curve gives (see Eritrotsitometriya).

Main function E. transport of oxygen and carbonic acid is. Erythrocytes participate in regulation of acid-base equilibrium in an organism, and also ionic balance of plasma, a water salt metabolism of an organism. They play an important role in regulation of activity of coagulant system of blood (see. Coagulant system of blood). Whole E., as well as thrombocytes (see), influence formation of thromboplastin. Emergence in the circulating blood destroyed E. can promote hypercoagulation and a thrombogenesis. AA. actively exchange lipids with a blood plasma, adsorb and transport to fabrics various amino acids, biologically active agents, etc.

Biochemistry, immunology, aging and destruction of erythrocytes. Solid residue mature E. contains apprx. 95% of hemoglobin, the rest falls to the share of other substances (lipids, negemoglobinovy proteins, carbohydrates, salts, enzymes, etc.). In structure E. negemovy iron, phosphorus, sulfur, zinc, copper, lead, tin, manganese, aluminum, silver, potassium, sodium, magnesium, chlorine and NSOD anions, НРО^, etc. enter. In erythrocytes, despite the lack of a cycle tricarboxylic to - t (see. Tricarboxylic acids a cycle) and systems of tsitokhrom (see), there is a generation of ATP, education and destruction of geksozofosfat and pentozofosfat, education, oxidation and recovery of various nucleotides. Along with it in E. a number of the substances important for life activity of cells, napr, glutathione is synthesized (see). Erythrocytes of the person contain more than 140 enzymes. Metabolism E. it is presented by generally anaerobic glycolysis (see). Distinctiveness of glycolysis in E. in comparison with other cells development of a significant amount 2,3-diphosphoglyceric to - you is, regulating turned sour natively - the connecting function of hemoglobin. Except glycolysis in E. there is a direct oxidation of glucose — foams-tozofosfatny a cycle (see. Carbohydrate metabolism), 10 — 11% of all power metabolism of a cell fall to the share to-rogo.

Average life expectancy E. makes about 120 days. At patol. states there can be a relative shortening of average life expectancy E., caused not only by accidental destruction of cells, but also acceleration of the process of aging * In this regard it is necessary to distinguish average life expectancy E. and average potential viability of a cell. On viability and bio-energetics E. significantly structural modification of lipids of a plasmolemma E influences., consisting in increase in fraction of the phospholipids (see Phosphatides) containing unsaturated fatty acids (see). It is established that average life expectancy E. is in inverse relation from intensity of peroxide oxidation of lipids in a plasmolemma E., therefore average life expectancy E. and at inhabitants of various geographical regions, and also at extreme loads of a healthy organism significant differences have a daily erythrocytopoiesis. At the same time fiziol. quantitative contents E. in blood it is reached by an equilibration of processes of destruction and regeneration of erythrocytes.

In process of aging E. metabolism of a cell is broken; content of proteins, lipids and glycoproteins decreases. Utilization of glucose decreases approximately by 3 times, concentration of ATP, NAD-N, NADF «N,

2,3-diphosphoglyceric to - you and glutathione decreases that leads to secondary destructive changes E. (sferulyation and loss of elasticity). Decrease in quantity sialine to - you as a part of glycoproteins involve change of the major properties of a surface E. (density of electric charge, antigenicity and reception). In this case ability E increases. to agglutination.

During the maturing and aging E. antigenic properties of its surface change. Density of antigenic determinants on a surface old E. is much higher, than on a surface of young people. Assume that with loss sialine to - you the glycoprotein complexes having ability to contact IgG then macrophages and lymphocytes killers «are unmasked» (see. Immunocompetent cells) «learn» the «marked» erythrocytes and destroy them. In blood it is quite often possible to observe spherical E., the adsorbed proteinaceous complexes bearing on the surface (fig. 1, c). Autoimmune cellular mechanism fiziol. destructions E. it is studied not completely.

The proteins of erythrocytes which became for one reason or another antigens for the organism cause formation of anti-erythrocyte autoantibodies like agglutinins, hemolysins and opsonins. In a wedge, prakti - the greatest value has definition of agglutinins, to-rye are subdivided into vhole and monovalent antibodies (see Antibodies, Hemagglutination). Vhole antibodies, connecting to antigens E., cause agglutination and destruction E., what occurs, e.g., at the hemolitic anemia caused by Holodov hey that antibodies. Monovalent antibodies, blocking antigens on a surface E., do not lead to development of hemagglutination in the salt environment and direct destruction of a cell, but considerably reduce duration of her life. The most frequent kind of these antibodies are the incomplete thermal agglutinins capable to cause autoimmune hemolitic anemia. Monovalent antibodies can be fixed on E. and to be in a blood plasma in a stand-at-ease. Apply to detection of the first forward reaction of Koombs, the second — indirect reaction of Koombs (see Koombs reaction). Unlike a miss of agglutinins autohemolysins (see Hemolysis) destroy E. with the participation of a complement (see) directly in a blood channel; among them acid hemolysins and two-phase hemolysins of Donat — Landshtey-nera have major importance (see. Hemolitic anemia). Definition of anti-erythrocyte autoantibodies plays an important role in diagnosis and treatment of autoimmune hemolitic anemias.

At repeated hemotransfusions the antieritro-cytic isoantibodies (see Blood groups, the Rhesus factor) which are according to the serological characteristic agglutinins can be formed. Agglutination E. it is observed at a number of viral diseases since viruses contain specific hemagglutinins (see Agglutination, Hemagglutination).

Methods of a research of erythrocytes. Calculation of number E. blood make in various ways. Total quantity E. count in 1 mkl blood in a cytometer under a microscope (see cytometers), a colorimetric method, by means of automatic counters. Total amount circulating E. define proceeding from the volume of the circulating blood and gematokritny number (see). The volume of the circulating blood is established more often by tracer techniques by introduction to blood of radioactive phosphorus (32P), chrome (51 Sg), albumine, marked 1311, etc. Indicators of volume of the circulating blood and the volume circulating E. have great diagnostic value at different blood losses and disturbance of blood circulation.

An assessment of a condition of red blood can be given on the basis of a complex of researches: establishments of amount of hemoglobin, number of erythrocytes, their morphology and intensity of coloring. In this regard determine the average content of hemoglobin in one erythrocyte and a color indicator (see Gemogrmma). The morphology is studied in the painted blood smears by means of svetooptichesky and supermicroscopes. Methods of coloring across Romanovsky — to Gimza (see Romanovsky — Gimza a method) and on Nokhta are the most widespread. The great value in a wedge, practice has definition of ROE (see Sedimentation of erythrocytes) and resistance E. to hypotonic solutions, chemical and physical impacts (see Hemolysis). Cytochemical, biochemical and immunological researches E. carry out for detection of pathology of a red hemopoiesis and definition of its character (see Marrow, Blood).

It is normal of change of erythrocytes also at pathology. The quantity of erythrocytes in

1 mkl blood of newborns, according to various researchers, fluctuates from 4,5 to 7,5 million; the greatest number E. it is observed during the first hours lives (7,5 million), then the quantity them quickly decreases and to 12 — to the 14th day of life usually reaches 4,9 — 5,0 million. In the first 5 — 7 days of life at children the clear anisocytosis is noted, often there are a poikilocytosis and a polikhromato-filiya. At children from 1 year to 2 years, and also from 5 to 7 years and from 12 to 14 years big individual fluctuations of number of erythrocytes come to light. Gradually with age (usually after 16 years) stable sizes for all parameters of erythrocytes are established. Persons of advanced and senile age have number E. decreases on average to 3,8 — 4,0 million in 1 mkl blood. Osmotic resistance E. in hypotonic salt solutions at newborns and children of chest age is higher, than at children of advanced age and at adults. Hemoglobin E. at newborns consists generally of fetalis hemoglobin (70 — 90%). By 2 years of life it is almost completely replaced with hemoglobin of «adults». Despite high metabolic activity E., newborns have an average life expectancy E. it is reduced at the expense of the strengthened oksidation and a peroksidation of cellular structures, first of all phospholipids of a plasmolemma. For all population E. the growing old organism decrease in ATP, NAD-N,

2,3-diphosphoglyceric to - you, osmotic and acid resistance E is characteristic., however shortenings of average life expectancy E. at persons of advanced and senile age it is not observed. Functional and structural inadequacy E. and related variability of contents E. in blood in ontogenesis, and also at various individuals is defined by metabolic activity of cells, antioxidant - ache protection of cellular structures and stability E. to hemolysis. In this regard on quantitative and qualitative parameters E. almost healthy person the great influence is exerted by genetic and ecological factors.

AA. at them patol. regeneration or the increased destruction may contain various inclusions. So, basphilic stippling E., opened by P. Ehrlich in 1886, has a cytoplasmatic origin; unlike basphilic substance of reticulocytes it is located on the periphery E. also it is painted by all dyes used during the processing of blood smears. Basphilic stippling comes to light as punctulate granularity of blue color; most often it meets at lead poisoning.

V E. find so-called little bodies of Joly and Cabot's ring, to-rye are the remains of kernels. Joly's little bodies meet in E. in the form of separate kernels of 1 — 2 microns \they, as well as Cabot's rings, are painted azurofilno and bazofil-but. Emergence them is caused by disturbance of enucleation (pushing out) of a kernel from a normoblast. Joly's little bodies meet most often after removal of a spleen. Cabot's rings have sometimes the form of the eight or a racket, meet at pernicious anemia.

At different types of malaria in E. the shyuffnerovsky granularity having an appearance of small azurophilic specks and larger uneven granularity of dark-violet color — Maurer's maculation comes to light.

Heinz's little bodies — Ehrlich are defined in E. at usual coloring of blood smears as small roundish formations (inclusions) of bright red color, at supravital coloring they have blue color. Formation of these little bodies is caused by coagulation of polypeptide chains of a molecule of hemoglobin at various patol. the states connected with intoxication of an organism, in particular at poisoning with aniline dyes, hemolitic poisons, and also at enzymopathies (see Enzimopenichesky anemia) or in case of presence in E. unstable haemo globins (see Hemoglobin, t. 10, additional materials; Hemoglobinopathies).

Sometimes in E. grains of hemosiderin, such E meet. call siderocytes, increase in their quantity is observed at nek-ry diseases, napr, at zhelezorefrakterny anemia (see).

340 ERLANGER


At various patol. states quantity E. can decrease, napr, at anemias, or raise (e.g., see the Polycythemia, Hyperglobulias, the Hyperglobulia hereditary and family).

See also Hemopoiesis, Blood. Bibliography: And sh to both N and z and I. Ya. Eritrotsit and an internal thromboplastinopoiesis, L., 1977; Age physiology, under the editorship of V. N. Nikitin, page 68, L., 1975; Istamanova T. S., Diamonds B. And. and To and N and e in S. V. Functional hematology, L., 1973; Kinetic aspects of a hemogenesis, under the editorship of G. I. Kozints and E. D. Goldberg, page 80, Tomsk, 1982; Kliorin A. I. and Tiunov L. A. Functional inadequacy of erythrocytes, L., 1974;

To about r at e in P. A. Gemoglobin, M., 1964; Crimean L., H e with t and y-to about G. V. and R y and l about in A. G. Raster submicroscopy of vessels and blood, M., 1976; M and r and h e in A. G., and d river. Interrelation of processes of an erythrogenesis, eritrodiyerez and peroxide oxidation of lipids of membranes of erythrocytes, Vestn. USSR Academy of Medical Sciences, No. 11, page 65, 1983; Membranes and a disease, under the editorship of L. In a fox, etc., the lane with English, M., 1980; Mosyagina E. H. Erythrocyte balance is normal also of pathology, M., 1962; Hereditary

anemias and hemoglobinopathies, under the editorship of Yu. N. Tokarev, etc., page 23, M., 1983; The Normal hemopoiesis and its regulation, under the editorship of N. A. Fedorov, M., 1976; Pukhova Ya. I. Autoimmune cellular mechanism of fyziologichesky destruction of erythrocytes, Novosibirsk, 1979; Ryabov S. I. Fundamentals of physiology and pathology of an erythrogenesis, L., 1971; V. V. and Gribov I. A. Falcons. Indicators of peripheral blood at healthy people, the Lab. business, No. 5, page 259, 1972; Physiology of system of blood, Physiology of an erythrogenesis, under the editorship of V. N. Chernigovsky, page 211, 274, L., 1979; The Person, Medicobiological data, the lane with English, page 45, M., 1977; To and at M. M.,

and. lake of Antigenicity, storage and aging,

physiologic autoantibodies to cell membrane and serum proteins and the senescent cell antigen, Molec. cell. Biochem., v. 49, p. 65, 1982; Red cell shape, ed.

by M. Bessis and. lake, N. Y., 1973.

A. G. Marachev.

Яндекс.Метрика