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Circulatory system The internal environment of the body. Blood
Internal environment of the body Blood Tissue fluid Lymph
Maintaining relative composition consistency internal environment the body is called homeostasis
The meaning of blood: The relationship of all organs in the body; Movement and distribution of nutrients between organs; Ensuring gas exchange between cells and environment; Removing harmful metabolic products from the body; Body protection (immunity); Thermoregulation
The human body contains approximately 5-6 liters of blood
Blood Plasma 60% Formed elements Erythrocytes Leukocytes Platelets
Inorganic substances Organic substances Water Mineral salts 0.9% Proteins Glucose Vitamins Hormones Decomposition products Fatty substances Blood plasma
Functions of blood plasma: Distribution of nutrients throughout the body; Removing harmful metabolic products from the body; Participation in blood clotting (fibrinogen protein)
BLOOD PLASMA Formed elements erythrocytes leukocytes PLATELETS
In the microscope eyepiece...
Red blood cells
Formed elements of blood Formed elements Quantity in 1 mm 3 Life expectancy Structure Where they are formed Functions Red blood cells 5 million. 120 days. A biconcave disc, covered with a membrane on the outside, containing hemoglobin inside, without a nucleus. Red bone marrow Transfer of oxygen and carbon dioxide
Blood in a test tube
Movement of red blood cells
Effect of the salt composition of the medium on red blood cells 2.0% 0.9% 0.2% 2.0% - hypertonic solution 0.9% - physiological solution 0.2% - hypotonic solution
Platelets
Formed elements of blood Formed elements Quantity In 1mm 3 Life expectancy Structure Where they are formed Functions Platelets 200-400 thousand. 8-10 days. Fragments of large bone marrow cells. Red bone marrow. Blood clotting.
The structure of a blood clot, fibrin threads, erythrocytes, leukocytes, serum
Conditions for blood clotting Injury of blood vessels Fibrin Fibrinogen Thromboplastin + Ca + O 2 Prothrombin Thrombin
Fibrinogen in the blood
Leukocytes
Formed elements of blood Formed elements Quantity In 1mm 3 Life expectancy Structure Where they are formed Functions Leukocytes 4-9 thousand. From several hours to 10 days. The shape is variable; they consist of a nucleus and cytoplasm. Red bone marrow. Protection.
LEUCOCYTES LYMPHOCYTES PHAGOCYTES B - cells T - cells Antibodies Special substances combine with bacteria and make them defenseless against phagocytes cause the death of bacteria and viruses Phagocytosis Immune reaction
Pinocytosis Phagocytosis
Pinocytosis is the absorption of liquid droplets by a cell. Phagocytosis – absorption of solid particles by a cell (possibly bacteria and viruses act as particles)
Mechnikov Ilya Ilyich (1845 - 1926) An outstanding biologist and pathologist. In 1983 Discovered the phenomenon of phagocytosis. In 1901 In his famous work “Immunity in Infectious Diseases,” he outlined the phagocytotic theory of immunity. He created a theory of the origin of multicellular organisms and studied the problem of human aging. In 1998 Awarded the Nobel Prize.
Lymphocytes LYMPHOCYTES B - cells T - cells Antibodies cause the death of bacteria and viruses Immune reaction combines with bacteria and makes them defenseless against phagocytes Special substances
What does a drop of blood tell? Blood analysis is one of the most common methods of Medical diagnostics. Just a few drops of blood provide important information about the state of the body. A blood test determines the number of blood cells, hemoglobin content, the concentration of sugar and other substances, and the erythrocyte sedimentation rate (ESR). If there is an inflammatory process in the body, the ESR increases. The ESR norm for men is 2-10 mm/h, for women 2-15 mm/h. When the number of red blood cells or hemoglobin in the blood decreases for any reason, a person experiences long-term or short-term anemia.
Laboratory work “Examining human and frog blood under a microscope” Tasks: Examine red blood cells on a frog blood sample. Find out how they differ. Draw the frog's red blood cells in your notebook. Examine a human blood sample and find red blood cells in the field of view of the microscope. Draw these blood cells in your notebooks. Find the differences between human red blood cells and frog red blood cells. Whose blood, human or frog, will carry more oxygen per unit time? Why?
Effect of nicotine
Effect of alcohol
The internal environment of the body is formed by: A – blood, lymph, tissue fluid B – body cavity C – internal organs D – tissues that form internal organs And now - a test!
2. The liquid part of the blood is called: A - tissue fluid B - plasma C - lymph D - physiological solution 3. All body cells are surrounded by: A - lymph B - sodium chloride solution C - tissue fluid D - blood
4. From tissue fluid is formed: A – lymph B – blood C – blood plasma D – saliva 5. The structure of red blood cells is associated with the function they perform: A – participation in blood clotting B – neutralization of bacteria C – oxygen transfer D – production of antibodies
6. Blood clotting occurs due to: A - narrowing of capillaries B - destruction of red blood cells C - destruction of leukocytes D - formation of fibrin 7. With anemia in the blood, the content of: A - blood plasma B - platelets C - leukocytes D - red blood cells decreases
8. Phagocytosis is the process of: A – absorption and digestion of microbes and foreign particles by leukocytes; B - blood clotting C - reproduction of leukocytes D - movement of phagocytes in tissues 9. Antigens are called: A - proteins that neutralize the harmful effects of foreign bodies and substances B - foreign substances that can cause an immune reaction C - blood cells D - a special protein called Rh factor
10. Antibodies are formed by: A – all lymphocytes B – T-lymphocytes C – phagocytes D – B-lymphocytes
Key to self-test 1 – A 6 – D 2 – B 7 – D 3 – C 8 – A 4 – A 9 – B 5 – C 10 - D
Tissue fluid is a component of the internal environment in which all cells of the body are directly located. Composition of tissue fluid: Water - 95% Mineral salts - 0.9% Proteins and other organic substances - 1.5% O 2 CO 2
Lymph Excess tissue fluid enters the veins and lymphatic vessels. In the lymphatic capillaries it changes its composition and becomes lymph. Lymph moves slowly through the lymphatic vessels and eventually enters the blood again. Lymph first passes through special formations - lymph nodes, where it is filtered and disinfected, enriched with lymphatic cells. Movement of blood and tissue fluid in the body
General functions of blood: transport, homeostatic and regulatory. The total amount of blood in relation to body weight in newborns and adults. The concept of hematocrit; physical and chemical properties of blood. Protein fractions of blood plasma and their significance.
presentation, added 01/08/2014
System for regulating the aggregate state of blood. Blood coagulation and anticoagulation systems. The reaction of the vascular wall in response to damage. Plasma coagulation factors. The role of vascular-platelet hemostasis. Ways of splitting a blood clot.
presentation, added 02/15/2014
The volume of blood in a living organism. Plasma and formed elements suspended in it. Major plasma proteins. Red blood cells, platelets and leukocytes. Basic blood filter. Respiratory, nutritional, excretory, thermoregulatory, homeostatic functions of blood.
presentation, added 06/25/2015
Complete blood count: norms, interpretation of the main indicators: hemoglobin, leukocytes, neutrophils, platelets, ESR. Stages of blood clotting. Physiological forms of hemoglobin, its pathological forms. Reasons for increased plasma creatine kinase activity.
presentation, added 04/04/2016
Internal environment of the body. The main functions of blood are liquid tissue consisting of plasma and blood cells suspended in it. The importance of plasma proteins. Formed elements of blood. The interaction of substances leading to blood clotting. Blood groups, their description.
presentation, added 04/19/2016
General characteristics and functional characteristics of various blood cells: red blood cells, hemoglobin, leukocytes. The main factors influencing the number of red blood cells, conditions associated with their excess and deficiency. Hemolysis: principles and stages of progression.
presentation, added 01/26/2014
Brief description blood clotting phases. Coagulation mechanism of hemostasis. Blood clot retraction and fibrinolysis. Objectives of the first anticoagulant system. Regulation of blood clotting. Human blood groups. General concept about the Rh factor.
abstract, added 03/10/2013
Analysis of blood cells: red blood cells, leukocytes, platelets. Hemoglobin and its functions in the body. Granulocytes, monocytes and lymphocytes as components of leukocytes. Pathologies in the composition of blood, their impact on the functions of the human body.
abstract, added 10/06/2008
Analysis of the internal structure of blood, as well as its main elements: plasma and cellular elements (erythrocytes, leukocytes, platelets). Functional characteristics of each type of blood cell element, their life expectancy and significance in the body.
presentation, added 11/20/2014
Composition and properties of blood, constituent elements: erythrocytes, leukocytes, platelets, their properties. Brief information on organogenesis. Blood circulation of the fetus and newborn, its principles and significance. Age-related features of the blood system in children and adolescents.
HematocritThe viscosity (internal friction) of blood is
property on which blood movement depends. So
How is resistance to blood flow proportional to
viscosity,
A
viscosity
proportional
hematocrit, then an increase in hematocrit may
lead to additional stress on the heart.
If the viscosity of H2O = 1 mPa s at 20°C:
blood plasma viscosity = 1.7-2.2 mPa s;
viscosity of whole blood ~ 5 mPa s.
1 Pa = 1 kg/(m s2)
blood
Dear students, we provide you with methodological materials - presentations of lectures on physiology, which will help you in your independent study of some topics. Physiology For groups of SB ISMD, Department of Physical Education Teacher: Candidate of Medical Sciences, Professor Arapko L.P. Physiology of Blood Physiology of Blood Blood, lymph, tissue, spinal, pleural, joint and other fluids form the internal environment of the body. The internal environment is distinguished by the relative constancy of its composition and physicochemical properties, which creates optimal conditions for the normal functioning of the body's cells. A little from history The concept of the constancy of the internal environment of the body was first formulated more than 100 years ago by the physiologist Claude Bernard. In 1929, Walter Cannon coined the term homeostasis. Homeostasis is understood as both the dynamic constancy of the internal environment of the body and the regulatory mechanisms that ensure this state. In 1939 G.F. Lang created the concept of blood. system Respiratory Transport Trophic Main functions of blood Thermoregulatory Regulatory Protective Homeostatic Excretory Volume and physicochemical properties of blood Blood volume - the total amount of blood in the body of an adult is on average 6 - 8% of body weight, which corresponds to 5 - 6 liters. An increase in total blood volume is called hypervolemia, a decrease is called hypovolemia. Osmotic pressure of blood - the force with which a solvent passes through a semi-permeable membrane from a less to a more concentrated solution. Oncotic pressure of blood - part of the osmotic pressure created by plasma proteins. Hemostasis system Blood circulates in the bloodstream in a liquid state. In case of injury, when the integrity of the blood vessels is compromised, the blood must clot. The RAS system, the regulation of the aggregate state of the blood, is responsible for all this in the human body. The following are involved in stopping bleeding: blood vessels, tissue surrounding the vessels, physiologically active plasma substances, blood cells; the main role belongs to platelets. And all this is controlled by a neurohumoral regulatory mechanism. Most plasma blood coagulation factors are formed in the liver. According to modern concepts, 2 mechanisms are involved in stopping bleeding: vascular platelet and coagulation. Vascular-platelet hemostasis Thanks to this mechanism, bleeding from small vessels with low blood pressure stops. In case of injury, a reflex spasm of damaged blood vessels is observed, which is further supported by vasoconstrictor substances (serotonin, norepinephrine, adrenaline) released from platelets and damaged tissue cells. Coagulation hemostasis Blood coagulation is a chain enzymatic process in which the activation of coagulation factors and the formation of their complexes sequentially occur. The essence of blood clotting is the transition of the soluble blood protein fibrinogen into insoluble fibrin, resulting in the formation of a durable fibrin thrombus. Fibrinolysis Fibrinolysis is the process of splitting a fibrin clot, as a result of which the lumen of the vessel is restored. Fibrinolysis begins simultaneously with clot retraction, but proceeds more slowly. This is also an enzymatic process, which is carried out under the influence of plasmin (fibrinolysin). Anticoagulation mechanisms Along with substances that promote blood clotting, there are substances in the bloodstream that prevent hemocoagulation. They are called natural anticoagulants. Some anticoagulants are constantly in the blood. These are the primary anticoagulants. Secondary anticoagulants are formed during the process of blood clotting and fibrinolysis. Blood groups Group I (O) – there are no agglutinogens in erythrocytes, plasma contains agglutinins a and b; Group II (A) – erythrocytes contain agglutinogen A, plasma contains agglutinin b; Group III (B) – agglutinogen B is found in erythrocytes, agglutinin a is found in plasma; Group IV (AB) – agglutinogens A and B are found in erythrocytes, there are no agglutinins in plasma. Rhesus system K. Landsteiner and A. Wiener in 1940 discovered an antigen in the erythrocytes of the rhesus monkey, which they called the Rh factor. This antigen is also found in the blood of 85% of people of the white race. In some peoples, for example, Evens, the Rh factor is found in 100%. Blood containing the Rh factor is called Rh positive (Rh+). Blood that lacks the Rh factor is called Rh negative (Rh-). The Rh factor is inherited.
Content. 1. Concept of the blood system. Blood functions. Blood volume and distribution. 2. Composition of mammalian blood. Plasma and serum. 3. Physico-chemical properties of blood.
Blood is a type of connective tissue that, together with lymph and tissue fluid, makes up the internal environment of the body.
The idea of blood as a system was created by G. F. Lang in 1939. This system included four components: peripheral blood circulating through the vessels, hematopoietic organs, hematopoietic organs, and the regulatory neurohumoral apparatus.
The blood system has a number of features: dynamic, i.e. the composition of the peripheral component can constantly change; lack of independent meaning, since it performs all its functions in constant motion, i.e. it functions together with the circulatory system. its components are formed in various organs.
Regulatory function Thermoregulatory Humoral regulation Maintaining the constancy of the internal environment of the body Regulation of hematopoiesis, etc.
Blood volume and distribution. Blood volume in animals averages 7 -9% of body weight (5 -13%) Cattle 7% (40 -50 l) Horses 7 -10% (60 -80 l) Sheep 7% (7 -10 l) Pig 5 -6% (4.5 -6.5 l) Poultry 10% (180 -315 ml) Dog 8 -9% (0.4 - 1 l) Cat 7% (140 -280 ml) Human 7% (4 , 5 -5 l)
Blood in the body is in the form of Circulating - 55 -60% of the total blood volume Deposited - 40 -45% of the total blood volume
Blood depot Capillary system of the liver (15 -20%) Spleen (15%) Skin (10%) Capillary system of the pulmonary circulation (temporary depot)
Plasma predominates in the circulating blood - 50–60%, the content of formed elements is 40–45%. In deposited blood, on the contrary, plasma is 40–45%, and formed elements are 50–60%
2. Composition of mammalian blood. Plasma and serum. Blood consists of plasma - the liquid part; and formed elements - cells. To determine the percentage of plasma and formed elements, the hematocrit is calculated.
Blood Plasma 55 -60% Formed elements 40 -45% Water 90 -92% Dry matter 8 -10% Organic Substances proteins, nitrogen-containing substances of non-protein nature, nitrogen-free organic components, enzymes Inorganic Substances (Anions and cations) Red blood cells Leukocytes Platelets
Blood plasma proteins make up 7–8% of the dry residue Hyperproteinemia - with an increase in protein concentration Hypoproteinemia - with a decrease Paraproteinemia - with the appearance of pathological proteins Dysproteinemia - with a change in their ratio
Normally, plasma contains albumin and globulins. Their ratio is determined by the protein coefficient, which is 1.5–2.0.
Albumins make up about 60% of all plasma proteins; they are synthesized in the liver; they perform a nutritional function; they are a reserve of amino acids for protein synthesis; they provide the suspension property of the blood, since they are hydrophilic proteins and retain water; participate in maintaining colloidal properties due to the ability to retain water in the bloodstream; transport hormones, cholesterol, inorganic substances, etc.
With a lack of albumin, tissue swelling occurs (up to the death of the body) - hungry edema.
Globulin concentration ranges from 30–35%; they are formed in the liver, bone marrow, spleen, and lymph nodes.
During electrophoresis, globulins break down into several types: Fraction alpha -1 - globulins Fraction alpha -2 - globulins Fraction beta globulins Fraction gamma globulins
Functions of globulins 1) protective (immunoglobulins, fibrinogen, plasminogen); 2) transport (haptoglobin and ceruloplasmin); 3) pathological (interferon (formed during the introduction of viruses), C-reactive protein).
Organic substances in blood plasma also include non-protein nitrogen-containing compounds (amino acids, polypeptides, urea, uric acid, creatinine, ammonia), nitrogen-free organic substances: glucose, neutral fats, lipids, enzymes that break down glycogen, fats and proteins, proenzymes and enzymes involved in processes of blood coagulation and fibrinolysis.
Inorganic substances in plasma make up 0.9 – 1%. These substances mainly include the cations Na+, Ca 2+, K+, Mg 2+ and the anions Cl -, HPO 4 2 -, HCO 3 -. regulate osmotic pressure; support p. H blood; participate in the stimulation of the cell membrane.
Body fluids are formed from blood plasma: vitreous fluid, anterior chamber fluid, perilymph, cerebrospinal fluid, coelomic fluid, tissue fluid, blood, lymph.
Blood serum = plasma-fibrinogen blood serum is a yellowish liquid that separates from the clot, consisting of fibrin and cellular elements. The process of obtaining serum is called defibrination, that is, the release of plasma from fibrin
Blood serum is most often used in the following tests: Biochemical blood test Blood test for infectious diseases Test to evaluate the effectiveness of vaccination Hormone levels
Immune sera are obtained from the blood serum of animals and people immunized with certain antigens, which are used for the diagnosis, treatment and prevention of various diseases.
3. The physicochemical properties of blood are determined by its composition: 1) suspension; 2) colloidal; 3) rheological; 4) electrolyte.
The suspension property (erythrocyte sedimentation rate) is associated with the ability of formed elements to be suspended. The colloidal property (oncotic pressure) is provided mainly by proteins that can retain water (lyophilic proteins). Electrolyte properties (osmotic pressure and blood reaction) are associated with the presence of inorganic substances. Rheological ability (viscosity, density) provides fluidity and affects peripheral resistance.
Rheological properties of blood Viscosity If the viscosity of water is taken as one, then the viscosity of whole blood is 3-6 times greater. Cattle 4, 7 Pig 5, 7 Horse 4, 3 Dog 5, 0 Chicken 5, 0 Rabbit 5,
Blood density (g/cm3) Relative density of whole blood 1.040-1.060, plasma – 1.025-1.034; erythrocytes – 1,080-1,040. Cattle, horse 1,055 Pig 1,048 Dog 1,056 Chicken 1,054 Rabbit 1,
The viscosity and density of blood is created by proteins and red blood cells. Indicators of viscosity and density of whole blood can increase with large losses of water in cases of prolonged diarrhea, vomiting, and profuse sweating.
Osmotic pressure of blood Osmotic pressure is the force that ensures the transition of a solvent through a semi-permeable membrane from less concentrated solutions to more concentrated ones.
The osmotic pressure of the blood is created by salts, glucose and is 7-8 atm. Which corresponds to the osmotic pressure of 0.9% sodium chloride solution (Na.CI), which is called saline.
Isotonic solutions - the osmotic pressure of which is equal to the osmotic pressure of blood plasma; Hypotonic solutions - the osmotic pressure of which is lower than the osmotic pressure of blood plasma; Hypertonic solutions - the osmotic pressure of which is higher than the osmotic pressure of blood plasma.
Regulation of osmotic pressure In the walls of blood vessels, in tissues, and in the hypothalamus, there are osmoreceptors that respond to changes in osmotic pressure. Their irritation causes a reflex change in the activity of the excretory organs and they remove excess water or salts that enter the blood.
Oncotic pressure of blood Oncotic pressure of blood depends on the proteins contained in the plasma (g. o. albumin). That is, the osmotic pressure of blood plasma proteins is called oncotic, and in warm-blooded animals it averages 30 mm Hg. Art. Oncotic pressure promotes the passage of water from tissues into the bloodstream, preventing the development of edema.
Blood reaction. Buffer systems. The blood reaction is determined by the concentration of hydrogen (H+) and hydroxyl (OH-) ions in the blood. The blood reaction is slightly alkaline (p. H 7.35 - 7.55) and is maintained at a relatively constant level due to the presence of buffer systems in the blood
The blood reaction is a rigid constant. Extreme limits p. H blood, compatible with life 7, 0 -7, 8. A shift in the reaction to the acidic side is called acidosis and is caused by an increase in hydrogen ions (H+) in the blood. A shift in the reaction to the alkaline side is called alkalosis and is associated with an increase in the concentration of hydroxyl ions (OH-).
Weak (lowly dissociated) acids and their salts formed by a strong base have buffering properties. Buffer systems include carbonate, phosphate, blood plasma proteins and hemoglobin (in practice)
The formed elements of blood include: erythrocytes - red blood cells; leukocytes - white blood cells; platelets are blood platelets. They account for 40-45% of the total blood volume.
PHYSIOLOGY OF ERYTHROCYTES Erythrocytes (from the Greek erythros - red) are red blood cells that make up the bulk of blood and determine its red color.
Structure of red blood cells Red blood cells of fish, amphibians, reptiles and birds are large, oval-shaped cells containing a nucleus. Mammalian red blood cells are smaller, lack a nucleus, and have the shape of biconcave discs (in llamas and camels, red blood cells are oval)
In an unfixed (native) preparation, red blood cells look like yellow round formations. In fixed and stained smears they are found as round cells of pink or grayish-pink color with clearing in the center
An erythrocyte consists of a stroma filled with hemoglobin and a semi-permeable (selectively permeable) protein-lipid membrane. The cell membrane of red blood cells is quite plastic, which allows the cell to deform and easily pass through narrow capillaries.
Functions of red blood cells: Respiratory Nutritional Protective Homeostatic Participation in the process of hemocoagulation They are carriers of various biologically active substances (enzymes, vitamins, hormones, metabolites). They carry group characteristics of blood (the presence of agglutinogens on the membrane).
The number of red blood cells in the blood of agricultural animals. The totality of all red blood cells in the body (circulating and deposited blood, bone marrow) is called erythron. The concept of “erythron” was introduced by the American W. Castle. Erythron is a closed system in which the destruction and formation of red blood cells occurs.
The number of erythrocytes in the blood of cattle 5 -10 million/μl Horse 6 -10 million/μl small cattle 7.5 -15 million/μl Pigs 5 -8 million/μl Dogs 5.4 -7.8 million/μl Cats 5, 8 - 10.7 million/µl In the same organism, the number of red blood cells per unit volume of blood can vary.
Increase in the number of red blood cells Erythrocytosis (from Latin erythrocytus - red blood cell, erythros - red, kytus - cell, osis - pathological increase) - an increase in the number of red blood cells, hemoglobin and an increase in hematocrit in the blood.
Classification (by origin): 1. Absolute (true), due to enhanced erythropoiesis: a) primary (congenital) - an independent, genetically determined disease (in animals -> isolated cases have been described in cattle and dogs); b) secondary, due to activation of erythropoiesis (hypoxic conditions): – physiological (high mountain areas); – pathological (pathology of the lungs, cardiovascular system, blood).
2. Relative (false), due to blood thickening – dehydration of the body, – redistribution of blood.
Decrease in the number of red blood cells Erythropenia (from Latin erythrocytus - red blood cell, erythros - red, kytus - cell, penia - pallor) - a decrease in the number of red blood cells and hemoglobin per unit volume of blood.
Anemia (anemia, or general anemia) is a clinical-hematological syndrome or an independent disease characterized by a decrease in the number of red blood cells and hemoglobin (or hemoglobin only) per unit volume of blood and changes in the qualitative composition of red blood cells.
Erythropenia occurs with prolonged underfeeding of animals, anemia of various etiologies, leukemia, tumors, infectious diseases, hemosporidiosis, liver and kidney diseases.
Properties of red blood cells Plasticity; Osmotic resistance; Availability of creative connections; Ability to settle; Aggregation; Destruction.
The plasticity of erythrocytes is the ability to undergo reversible deformation when passing through narrow capillaries and micropores. Plasticity is determined by the structure of the cytoskeleton, in which the ratio of phospholipids and cholesterol is very important. This ratio is expressed as a lipolytic coefficient and is normally 0.9. With a decrease in the amount of cholesterol in the membrane, a decrease in the plasticity and stability of red blood cells is observed.
The creative ability of erythrocytes is associated with their ability to transport various substances and carry out intercellular interactions.
Aggregation (sticking together) of red blood cells is associated with a slowdown in blood flow and an increase in blood viscosity. With rapid aggregation, “coin columns” are formed - false aggregates that disintegrate into full-fledged cells. With prolonged disruption of blood flow, true aggregates appear (blood sludge, sludge phenomenon), causing the formation of a microthrombus.
"Coin columns" of red blood cells. Linear or branched chains of erythrocytes - formations of “coin bundles”. Under normal conditions, this phenomenon is most often observed in horses, but this process can also be observed in most animals with inflammatory diseases. Horse blood smear; 50 x lens. Intercellular adhesion of erythrocytes. Formation of “coin columns” and agglutination.
Osmotic properties of erythrocytes. Hemolysis The ability of red blood cells to withstand various destructive influences is called resistance (stability) of red blood cells. The resistance of erythrocytes is determined in relation to solutions of sodium chloride of various concentrations, i.e. their osmotic resistance. Under normal conditions, red blood cells can withstand a decrease in Na concentration. Cl up to 0.6 -0.4%, not destroyed.
In hypertonic solutions (Na.Cl concentration more than 0.98-1%), red blood cells lose water and shrink at lower Na concentrations. Cl (hypotonic solutions) red blood cells are destroyed and hemoglobin is released into the plasma. In agricultural animals, the erythrocytes of small animals and pigs have the least resistance, and the highest - of birds and fish. IN summer period the resistance of erythrocytes in animals increases.
The destruction of the membrane of red blood cells and the release of hemoglobin from them is called hemolysis. Types of hemolysis: chemical: the membrane of red blood cells is destroyed by chemicals; mechanical: the membrane of red blood cells is destroyed by strong shaking; temperature: the membrane of red blood cells is destroyed under the influence of high and low temperatures;
radiation: the membrane of red blood cells is destroyed under the influence of X-rays and UV rays; osmotic: destruction of red blood cells in water or hypotonic solutions; biological: the membrane of red blood cells is destroyed by transfusion of incompatible blood, bites of poisonous snakes, insects.
In the body, hemolysis constantly occurs in small quantities when old red blood cells die. Red blood cells are destroyed in the spleen (“red blood cell cemetery”), liver, red bone marrow; the released hemoglobin is absorbed by the cells of these organs, and it is absent from the circulating blood plasma.
Erythrocyte sedimentation rate (reaction). The ability to settle is determined by the specific gravity of cells, which is higher than that of blood plasma. The erythrocyte sedimentation rate (ESR; ROE) characterizes the suspension properties of blood; Normally, it is low, due to the surface potential of the membrane and the presence of proteins in the albumin fraction.
ESR depends on the species, sex, age, physiological state of the animal and on changes in the physicochemical properties of the blood. The ESR of animals increases in the following sequence: MRS< КРС < птица < свиньи < лошади
ESR of healthy animals (mm/h): MRS - 0.5 -1.5 Dogs - 2 -6 Cattle - 0.5 -1.0 Pigs - 2 -9 Poultry - 2 -3 Horses - 40 -
The acceleration of erythrocyte sedimentation is facilitated by globulins, fibrinogen, mucopolysaccharides, the content of which increases in many inflammatory processes, infections, malignant tumors, kidney diseases and other pathologies. ESR increases greatly during pregnancy. A slowdown in ESR is observed with diarrhea, profuse sweating, physical activity, polyuria (increased urination), jaundice, and intestinal obstruction (ileus).
Destruction - destruction of red blood cells as a result of physiological aging (the average lifespan of red blood cells is 100 -120 days); characterized by: a gradual decrease in the content of lipids and water in the membrane; increased yield of N a+ and K+ ions; the predominance of metabolic changes; deterioration in the ability to restore methemoglobin to hemoglobin; a decrease in osmotic resistance, leading to hemolysis.
Hemoglobin and its compounds. Hemoglobin is a complex protein (chromoprotein), thanks to which red blood cells perform the respiratory function and maintain p. H blood.
Hemoglobin consists of two components: globin protein (96%); iron-containing heme (4%).
Globin is a protein like albumin. U different types In animals, it differs in amino acid composition, which determines differences in the properties of hemoglobin.
Heme complex compound of porphyrin with iron (unstable compound). The structure of heme is identical for hemoglobin of all animal species.
The content of Hb (g/l) in the blood of agricultural animals is: Cattle 80 -150 Horse 110 -170 Small cattle 80 -160 Pigs 100 -180 Dog 130 -19 0 Cat 90 -
In the process of transporting oxygen, hemoglobin changes its shape. In this case, the valency of the iron to which oxygen is added does not change, i.e., the iron remains divalent. The reaction of oxygen binding to hemoglobin is called oxygenation; the opposite process is called deoxygenation.
The main compounds of hemoglobin: I. PHYSIOLOGICAL: oxyhemoglobin (KH b 02) - a compound with oxygen; carbohemoglobin (C 0 2 MH 2 H b) - compound with carbon dioxide; reduced (reduced) hemoglobin - hemoglobin that has given up oxygen; deoxyhemoglobin (H + H b) is a compound with hydrogen ions.
II. PATHOLOGICAL: carboxyhemoglobin (H b CO) is a persistent compound with carbon monoxide; methemoglobin (Me t H b) - oxidation of iron to the trivalent state; glycosylated hemoglobin is a compound with glucose.
Types of hemoglobin: There are several forms of hemoglobin, which change during ontogenesis and differ in the structure of the protein part - globin (H b A, H b. F, H b P).
Initially, the embryo has embryonic (primitive) hemoglobin - H b P (the first months of intrauterine development). Then the fetus appears; fetal hemoglobin (fetal hemoglobin) - H b. F, which at the time of birth is replaced by definitive hemoglobin (adult hemoglobin) - H b A.
Color index: In clinical settings, it is customary to calculate the degree of saturation of red blood cells with hemoglobin. This is the so-called color index (CP). CP is important for diagnosing anemia of various etiologies.
The color index is the percentage of hemoglobin content to the number of red blood cells per unit volume of blood (1 mm3).
Normally, the CPU is 1 or close to it. Such erythrocytes are called normochromic. When CP is 0, 8 and below, erythrocytes are poorly saturated with hemoglobin and are called hypochromic. When the CP is above 1, the red blood cells are called hyperchromic
Oxygen capacity is the maximum amount of oxygen that can be bound to 100 ml of blood during the transition of hemoglobin to oxyhemoglobin.
Myoglobin In the skeletal and cardiac muscles of animals there is muscle hemoglobin - myoglobin. Due to its lower density than hemoglobin, its affinity for oxygen increases sharply. Therefore, myoglobin is exclusively adapted to oxygen storage.
This is important for supplying oxygen to muscles that perform work for a long time: the muscles of the wings of birds, the muscles of the limbs of warm-blooded animals, the muscles of mastication, and the heart muscle.
Myoglobin plays an important role in supplying oxygen to working muscles: it stores oxygen during muscle relaxation and releases it during contraction. There is a lot of myoglobin in animals that are under water for a long time, as well as in diving birds. Under the influence of loads, the myoglobin content increases. Myoglobin is the red color of muscles. There is no myoglobin in the breast muscles of chickens - white meat.
Physiology of leukocytes Leukocytes you (from GREEK λευκως - white and kýtos - cell, white blood cells) are a heterogeneous group of different appearance and functions of blood cells, identified on the basis of the absence of independent coloring and the presence of a nucleus.
The collection of mature and immature white blood cells (leukocytes) is called leukon. More than half of the leukocytes are located outside the vessels (in the intercellular space and bone marrow) due to the presence of a number of physiological features.
Properties of leukocytes: 1. Amoeboid motility; 2. Migration and diapidesis (the ability to penetrate the wall of intact vessels); 3. Phagocytosis (the ability to absorb and digest foreign agents).
Functions of leukocytes: The protective function is associated with the bactericidal and antitoxic effects of agranulocytes, participation in the processes of blood coagulation and fibrinolysis. The destructive effect is associated with the phagocytic activity of cells. Regenerative activity is associated with the processes of cell growth, differentiation, tissue regeneration, and promotes wound healing. The enzymatic function is associated with the presence of a number of enzymes (protease, peptidase, lipase, diastase, deoxyribonuclease). Leukocytes are destroyed in the mucous membrane of the digestive tract, as well as in the reticular tissue.
The total number of leukocytes in peripheral blood is significantly less than erythrocytes. In animals it is approximately 0.1 -0.2%, in birds - about 0.5 -1.0% of the number of red blood cells: Cattle 6 -10 thousand/µl Horse 7 -12 thousand/µl MRS 6 -11 thousand/ µl Pig 8 -16 thousand/µl
There are several types of leukocytes, differing from each other in size, the presence or absence of granularity in the cytoplasm, the shape of the nucleus, and other characteristics.
CLASSIFICATION OF LEUKOCYTES GRANULAR (GRANULOCYTES): the presence of granularity in the cytoplasm Basophils (stained with basic dyes) Eosinophils (stained with acidic dyes) Neutrophils (stained with basic and acidic dyes): Metamyelocytes (young) Banded Segmented NON-GRANULAR (AGRANULOCYTES): absence of granular spines in the cytoplasm Monocytes Lymphocytes
Neutrophils The main function is phagocytosis - the absorption of foreign organisms (for example, bacteria) or their parts. Neutrophils also secrete substances that have a bactericidal effect.
Eosinophils are capable of active movement, phagocytosis, as well as the uptake and release of histamine, which makes these cells integral participants in inflammatory and allergic reactions.
Basophils are involved in the formation of immediate allergic reactions. Basophils released from the bloodstream into the tissue are mast cells. Mast cells contain large number histamine, which, by causing swelling, helps limit the spread of infection and toxins. Secrete heparin.
Monocytes in tissues turn into macrophages. As macrophages, they participate in phagocytosis in immune reactions (process and present antigens to lymphocytes)
Lymphocytes T-lymphocytes are capable of destroying bacteria, tumor cells, and also influencing the activity of B-lymphocytes, which in turn are the main cells responsible for humoral immunity, that is, the production of antibodies.
Leukocytes Granular (granulocytes) Non-granular (agranulocytes) Neutrophils Basophils Eosinophils Lymphocytes Monocytes The percentage of leukocytes in the peripheral blood is called the leukocyte formula (leukogram, leukoformula). The leukogram has species differences and changes under various pathological conditions.
An increase in the number of leukocytes per unit volume of blood is called leukocytosis, leukemia; decrease - leukopenia.
Increase in the number of leukocytes: physiological leukocytosis (redistribution, neurohumoral); pathological (reactive, true); – absolute; – relative.
Physiological leukocytosis occurs as a result of the redistribution of blood in the vessels, the release of leukocytes from the depot; have a physiological origin, are short-lived, and are observed under certain conditions.
myogenic leukocytosis - during pregnancy (especially in the later stages), during childbirth, with muscle tension; static leukocytosis - with a rapid transition from a vertical to a horizontal position; digestive leukocytosis - 2-3 hours after eating food (in monogastric animals); emotional leukocytosis - with mental excitement, stress (associated with the release of adrenaline and its direct effect on the depot).
Pathological leukocytosis occurs when the bone marrow is irritated by a pathological agent, increased leukopoiesis, and is characterized by the appearance of young forms of leukocytes in the blood.
Types of pathological leukocytosis: infectious, observed in many infectious diseases, inflammatory processes; traumatic, with shock, after operations, traumatic brain injury; toxic, in case of poisoning with arsenic, mercury, carbon monoxide, tissue decay, necrosis; medicinal, taking certain medications (glucocorticoids, antipyretics, painkillers); posthemorrhagic, after heavy bleeding.
Relative leukocytosis is an increase in the number of one type of leukocyte without changing their total number per unit volume of blood: neutrophilia; eosinophilia; basophilia; lymphocytosis; monocytosis.
Decrease in the number of leukocytes: absolute leukopenia, with a decrease in the number of all leukocytes; relative, with decreasing individual species leukocytes: neutropenia; eosinopenia; lymphopenia; monocytopenia; agranulocytosis. It is difficult to take into account the decrease in the number of basophils due to their small number in the blood (the norm is 0 -1%)
Types of leukopenia: Temporary (redistribution), when lymphocytes gather in a depot (shock conditions); Permanent (true), associated with inhibition of leukopoiesis, increased destruction of leukocytes; Infectious-toxic (bacterial and viral infections, intoxication); Organic (ionizing radiation, tumor processes); Autoimmune (hypo-, aplastic anemia, repeated blood transfusion, hemotherapy); Deficiency (protein and amino acid starvation, hypovitaminosis)
Consequences: the main consequence of leukopenia is a weakening of the body's reactivity, caused by a decrease in the phagocytic activity of neutrophil granulocytes and the antibody-forming function of lymphocytes. This leads to an increase in the incidence of infectious and tumor diseases.
Platelets (blood platelets) are flat cells of irregular round shape with a diameter of 2 - 5 microns. Peripheral blood platelets are a fragment of a megakaryocyte cell, which, while still in the bone marrow, breaks down into 3000-4000 small oval-shaped particles - blood platelets. The platelet lacks a nucleus and most subcellular structures.
Platelets circulating in the blood have an oval or round shape, a smooth surface, activated - a stellate shape and filamentous processes - pseudopodia. Stages of contact activation of platelets: A - inactive platelet (discocyte, plate); B — platelets in the reversible stage of contact activation (spherical shapes with pseudopodia); B - platelet in the irreversible stage of adhesion (spread out form without internal contents - “platelet shadow”)
Properties of platelets: amoeboid motility; rapid destructibility; ability for phagocytosis; ability to adhesion (stick to a foreign surface); ability to aggregate (stick together).
Functions of platelets: The trophic function is to provide the vascular wall with nutrients, due to which the vessels become more elastic. The dynamic function consists in the processes of adhesion and aggregation of platelets when the vascular wall is damaged. Regulation of vascular tone is carried out due to the presence of mediators serotonin and histamine in the granules, which affect the tone and permeability of capillaries, thereby determining the state of histohematic barriers. Participation in blood coagulation processes is ensured due to the content of lamellar factors (PF - 1, 2, 3, 4, ...) in the granules, which polish hemostasis.
Platelet count Cattle 450 thousand/μl Horse 350 thousand/μl Small cattle 350 thousand/μl Pig 210 thousand/μl
An increase in the number of platelets (thrombocytosis) is observed during heavy muscular work, digestion, pregnancy and some pathological conditions.
A decrease in the number of platelets (thrombocytopenia) is noted in acute infectious diseases and shock conditions.
Physiology of the functioning of the hemostasis system. Hemostasis is a complex biological system that ensures, on the one hand, the preservation of blood in the bloodstream in a liquid aggregate state, and on the other hand, stopping bleeding and preventing blood loss from damage to blood vessels.
There are three links in the coagulation system of hemostasis: Hemostasis Coagulation system Vascular link Cellular (platelet-leukocyte) link Fibrin (plasma-coagulation) link
The main provisions of the modern theory of blood coagulation were developed by A. Schmidt in 1872. According to modern concepts, 2 mechanisms are involved in stopping bleeding: vascular-platelet (primary) hemostasis; plasma-coagulation (secondary) hemostasis.
Vascular-platelet hemostasis is primary, microcirculatory hemostasis stops bleeding in small vessels with low blood pressure and small lumen through the formation of a platelet plug.
Includes several stages: short-term vasospasm (reflex stimulation of vascular smooth muscles by the sympathetic nervous system); activation of endothelial cells; platelet adhesion to the wound surface; activation of adherent platelets and release reactions; platelet aggregation; retraction (compaction) of a platelet (white) thrombus.
Secondary, or coagulation hemostasis is a chain enzymatic process in which the activation of plasma coagulation factors and the formation of their complexes sequentially occur.
The essence is the transition of the soluble blood protein fibrinogen into insoluble fibrin, resulting in the formation of a durable fibrin (red) thrombus.
Coagulation (secondary) hemostasis occurs within a few minutes and occurs when large vessels are injured, when, after activation of vascular-platelet hemostasis, the process of enzymatic blood coagulation begins.
Clotting factors are designated by Roman numerals as they open. Activation of a factor is indicated by adding the letter “a”: I – Ia To stop bleeding, 10-15% of the normal concentration of most factors is sufficient, for example, II, V - XI.
Plasma coagulation factors I - fibrinogen (I a fibrin) II - prothrombin (II a thrombin) III - tissue thromboplastin IV - Ca 2+ V - proaccelerin (Va - accelerin) VI - excluded from classification = activated factor Va, VII - proconvertin VIII - antihemophilic globulin A (von Willebrand factor) IX - antihemophilic globulin B (Christmas factor) X - Stewart-Prower factor XI - plasma precursor of thromboplastin, or antihemophilic factor C (Rosenthal factor) XII - contact factor (Hageman) XIII - fibrin stabilizing factor XIV - Fletcher prekallikrein factor() XV - Fitzgerald factor (high molecular weight kininogen)
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Phases of coagulation hemostasis Phase I - formation of prothrombinase - internal (slow) path (5 - 8 min) - external (fast) path (5 - 10 s) Phase II - formation of thrombin (IIa) (2 - 5 s) Phase III - formation fibrin thrombus (2 - 5 s): Post-coagulation phase (about 70 min) - thrombus retraction
Anticoagulant system The fluid state of the blood is maintained due to its movement (which reduces the concentration of reagents), adsorption of coagulation factors by the endothelium and due to natural anticoagulants.
Primary anticoagulants are present in the blood before coagulation begins: antithrombin III heparin 1 -antitrypsin protein C thrombomodulin antithromboplastins
Secondary anticoagulants are formed during the process of blood coagulation and fibrinolysis: atithrombin I is fibrin, which adsorbs and inactivates thrombin, factors Va, Xa; Antithrombin VI is a product of fibrinolysis that blocks fibrinogen and fibrin monomer, thrombin and factor XIa.
Fibrinolytic system of hemostasis Fibrinolysis (prevents the formation and carries out lysis of fibrin thrombus formed in the process of constant local hemostasis, can be carried out in two ways: with the participation of plasmin without the participation of plasmin.
Non-plasmin version of fibrinolysis The non-plasmin version of fibrinolysis is carried out by fibrinolytic proteases of leukocytes, platelets, erythrocytes and antithrombin III in combination with heparin, which can directly break down fibrin.
Determination of the clotting time of whole unstabilized blood A vein is punctured with a needle without a syringe. The first drops of blood are released onto a cotton swab and 1 ml of blood is collected into 2 dry tubes. Turn on the stopwatch and place the test tubes in a water bath at a temperature of 37°C. After 2–3 minutes, and then every 30 seconds, the tubes are slightly tilted, determining the moment when the blood clots. Having determined the time of formation of a blood clot in each test tube, the average result is calculated.
In 1900, the Austrian researcher Karl Landsteiner, mixing red blood cells with normal blood serum from different people, discovered that with some combinations of serum and red blood cells from different people, agglutination (sticking together and settling into a cage) of red blood cells is observed, while with others it is not.
Antigens are substances that carry signs of genetically foreign information. Isoantigens (intraspecific antigens) are antigens that originate from one type of organism, but are genetically foreign to each individual. Antibodies are immunoglobulins formed when an antigen is introduced into the body.
The blood group is determined by isoantigens; in humans there are more than 200 of them. They are combined into group antigen systems, their carriers are erythrocytes. There are no isoantigens in the blood plasma of newborns. They are formed during the first year of life under the influence of substances supplied with food, as well as those produced by intestinal microflora, to those antigens that are not in its own red blood cells.
Isoantigens are inherited, constant throughout life, and do not change under the influence of external and internal factors.
The doctrine of blood groups is based on intraspecific biological differences between human and animal blood. These differences are manifested in the presence of specific proteins agglutinogens/isoantigens (on the surface of red blood cells) and agglutinins (in blood plasma). Depending on the combination of erythrocyte agglutinogens and plasma agglutinins, blood is divided into groups.
The main agglutinogens of human erythrocytes are agglutinogen A and agglutinogen B, and plasma agglutinins are agglutinin ά and agglutinin β.
The same agglutinogens and agglutinins (A and ά, B and β) are not found in the blood of the same organism. This would lead to an agglutination reaction (gluing and destruction of red blood cells) - an immune conflict.
There are four combinations of agglutinogens and agglutinins and, accordingly, four blood groups that are combined into the ABO system.
Approximately 35% of the population of central Europe has group I (0), more than 35% has group II (A), 20% has group III (B), about 8% has group IV (AB). 90% of the indigenous people of North America belong to group I (0); more than 20% of the population of Central Asia have III (B) blood group.
People with blood group I were previously considered universal donors, i.e. their blood could be transfused to all persons without exception. However, in people with blood type I, immune anti-A and anti-B agglutinins are found in a fairly significant percentage. Transfusion of such blood can lead to serious consequences and even death. These data served as the basis for transfusion of only single-group blood.
Rhesus factor The Rh antigenic system was discovered in 1940 by K. Landsteiner and A. Wiener. They discovered antigens in the erythrocytes of monkeys (rhesus macaques), to which, when introduced into the body of rabbits, corresponding antibodies were produced. This antigen was called the Rh factor.
Currently, six types of Rh antigens have been described. The most important are Rh. O(D), Rh’(C), Rh”(E). The presence of at least one of the three antigens indicates that the blood is Rh positive (Rh+).
Rh antigens are found in the blood of 85% of white people. In some Negroids, the Rh factor is 100%. In the aborigines of Australia (not a single antigen of the Rh system has been identified.
Blood containing the Rh factor is called Rh positive (Rh+). Blood in which the Rh factor is absent is called Rh negative (Rh-). The Rh factor is inherited. The peculiarity of the Rh system is that it does not have natural antibodies, they are immune and are formed after sensitization - contact of Rh- blood with Rh+.
During the initial transfusion of Rh- person with Rh+ blood, Rh conflict does not develop, because there are no natural anti-Rhesus agglutinins (antibodies) in the recipient’s blood. An immunological conflict according to the Rh antigenic system occurs when Rh- blood is repeatedly transfused into an Rh+ person, in cases of pregnancy when the woman is Rh- and the fetus is Rh+.
In addition to the antigens of the ABO system and the Rh factor, other agglutinins were found on the membrane of erythrocytes, which determine blood groups in this system. There are more than 400 such antigens, but highest value for the practice of blood transfusion they have the ABO system and the Rh factor.
Leukocytes also have antigens (more than 90). Practical significance have histocompatibility antigens, which play an important role in transplantation immunity.
Animal blood groups A large number of antigenic factors have been found in the erythrocytes of agricultural animals, which are designated in capital Latin letters (A, B, C, etc.). There are few or no natural antibodies in the blood plasma. Antigens, the inheritance of which is interdependent, make up the blood group system.
In cattle, 100 antigenic factors are determined, which are combined into 12 systems, in pigs - 50 antigens, 14 systems, in sheep - 7 systems, in horses - 8 systems, in chickens - 14 systems. Animals' genetic connections and origins are traced using blood groups. Connections between blood groups and the level of productivity and vitality have been established.
Animal species Number of antigens Number of blood group systems Cattle > 100 12 Pigs > 70 16 Sheep 30 8 Horses 30 8 Buffaloes 15 7 Dogs 15 11 Chickens 60 14 Turkeys
Blood groups of dogs and cats The following blood groups are found in dogs: DEA 1. 1 *DEA 1. 2 *DEA 3 DEA 4 DEA 5 DEA 6 *DEA 7 DEA 8 * - the most immunogenic blood groups.
Cats have 3 blood groups: A (II), B (III) and AB (IV). The most common is group A. Group B is not as common (more common in Abyssinians, Burmese, Persians, Somali cats, Scottish Folds, Exotics, Britons, Cornish Rex and Devon Rex). Group AB is extremely rare
Blood transfusion (hemotransfusion) Blood transfusion is the most effective remedy for heavy blood loss. It is also used for pernicious anemia, toxicosis, and some infectious diseases.
Under the influence of transfused blood in the recipient's body: blood pressure is equalized; the respiratory function of the blood is restored; hematopoiesis increases; blood clotting increases; general vitality increases.
In veterinary practice, blood transfusion is most often used to treat horses and small domestic animals. For transfusion, compatible blood from an animal of the same species is used. Transfusion of incompatible blood can cause transfusion shock (agglutination and hemolysis of red blood cells) and death of the animal.
Whole blood is transfused only in cases where blood loss exceeds 25% of the total volume. If the total blood loss is less than 25% of the total volume, plasma substitutes (colloid solutions) are administered.
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