Blood system firstly was proposed by Lung in 1936. It consist of - blood circulated through the...

Blood system firstly was proposed by Lung in 1936.

It consist of- blood circulated through the blood circulatory system - blood forming organs- blood destroying organs- regulatory apparatus.

Blood is a fluid connective tissue. • Blood consist of • - plasma • - blood cells: 1.erythrocytes, 2. leucocytes, 3.platelets.

1. Breathing function of blood.2. Trophic function of blood. 3. Excretory function of blood.4. Hormonal regulation.6. Temperature regulation.7. Maintaining the acid-base balance of tissues. 8. Supporting the water-electrolytic balance.9. Homeostasis function.10. Protecting the body from bacteria and other organisms that can cause diseases or other abnormal conditions.

Transport of: Gases, nutrients, waste productsProcessed moleculesRegulatory molecules

Regulation of pH and osmosisMaintenance of body temperatureProtection against foreign substancesClot formation

In adult in normal blood, relative to total body weight, is 6.8%. Newborns - 15%.Part of the blood is in the depot:liver - 20%, in the skin, subcutaneous vascular plexus - up to 10%, in the spleen - up to 1.5-2% of blood. Deposited blood in comparison with blood circulating in the vessels is 10-20 times slower than blood cells.

Human blood smearHuman blood smear

X 500

Erythrocytes In men – 4,0-5,1 Tera/L; in women – 3,7-4,7 Tera/L. The quantity of erythrocytes may be increase – in pregnancy, in physical training, mental work, in newborn or decrease. Leukocytes - 4-9 Giga/L. The number of leukocytes can increase – physical work, emotional load, in newborn, inflammation or decrease.Platelates - 180-320 Giga/L.

Human erythrocytes - nuclear-cells that are shaped like concave discs 4,5-10,5 microns in diameter (average diameter of erythrocyte 7,55 m). With this form of erythrocyte, its surface is greater than it would be in spherical form.

Quantitative parameters of Quantitative parameters of erythrocytes and their changeserythrocytes and their changes

“Erythron" introduced in 1936, Castle and Minot to refer to the all quantity of red blood cells in the body.Reduce the number of red blood cells called erythropenia. Increasing the number of red blood cells is called polycythemia. Under physiological conditions, polycythemia can be hereditary and acquired (for example, when staying in the mountains)

Transport function. Red blood cells carry: O2, CO2, NO, adsorbed proteins, drugs, physiologically active substances.Provide acid-base balance. Maintaining the ionic composition of the plasma.Hemostatic.

Production of Erythrocytes: Production of Erythrocytes: ErythropoiesisErythropoiesis

In adults, red blood cells are formed in the red bone marrow of flat bones nuclear stem cells, which goes through several stages :Common progenitor cell → uncommitted stem cell → committed stem cell → erythroblast (is the first cell , which can be morphologically identifiable ) → pronormoblast → early (basophilic) normoblast → intermidiate (polychromatorhylic) normoblast → late (eosinophilic) normoblast → reticulocyte → erythrocyte.

Bone marrow produces an hour about 1010 mature erythrocytes.For the formation of erythrocyte need:

1. iron ;2. vitamin B12 ;3. B9 folic acid ;

4. vitamin C;5. vitamin B6 ;6. Vitamin B2 ;

Regulation of erythropoiesis carried out by neural and humoral mechanisms, sympathetic innervation stimulates hematopoiesis and parasympathetic - brakes. Of great importance is the regulation of erythropoiesis erythropoietin. Hematopoiesis is enhanced by hormones front of the pituitary gland, adrenal glands, thyroid gland. Male sex hormones stimulate, increasing the sensitivity of bone marrow to erythropoietin, and women - inhibit erythropoiesis.

The body formed substances that inhibit erythropoiesis - inhibitors of erythropoiesis. Their content increases with the number of red blood cells, which do not meet the needs of the tissues for oxygen. Inhibitors of erythropoiesis lengthen cycle division erythroid cells, they inhibit the synthesis of hemoglobin.

Regulation and Requirements Regulation and Requirements for Erythropoiesisfor Erythropoiesis

Circulating erythrocytes – the number remains constant and reflects a balance between RBC production and destruction

Too few red blood cells leads to tissue hypoxiaToo many red blood cells causes undesirable blood viscosity

Erythropoiesis is hormonally controlled and depends on adequate supplies of iron, amino acids, and B vitamins

Water – 90 % Solids – 10 %Inorganic chemicals: sodium, calcium, potassium, magnesium, chloride, bicarbonate, phosphate, sulfate – 0,9 % Organic chemicals:Proteins: serum albumin, serum globulin, fibrinogen – 8 %Others: – 1,1 % Nonprotein nitrogenous substances: urea, uric acid, creatine, creatinine, ammonium salts, amino acidsNonnitrogenous substances: glucose, fats, cholesterol hormonesGases: oxygen, carbon dioxide, nitrogen

Components of Whole BloodComponents of Whole Blood

Withdraw blood and place in tube

1 2 Centrifuge

Plasma(55% of whole blood)

Formed elements

Buffy coat:leukocyctes and platelets(<1% of whole blood)

Erythrocytes(45% of whole blood)

• Hematocrit • Males: 40-48%

• Females: 36- 42%

Volume ratio of blood cells and plasma called hematocrit. Normally it is men 0,40-0,48 l / l (40-48%) in women - 0,36-0,42 l / l (36-42%).

One liter of plasma has 65-85 gram of proteins. Concentration of albumins is 35-50 g/L; globulins is alpha-1-globulins – 1-4 g/L, alpha-2-globulins – 4-8 g/L, beta-globulins – 6-12 g/L, gamma-globulins – 8-16 g/L; fibrinogen – 2-4 g/L.Plasma which are not contain fibrinogen called serum (it is necessary for understanding the immunology, therapy etc.)

Albumin: 80% defines oncotic pressure transfer bilirubin, urobilin , fatty acids , antibiotics , sulfonamides , are formed in the liver , 17 g per day.Globulin. In a fraction of α1- globulins are proteins associated with carbohydrates. The fraction of α2- globulins include protein ceruloplasmin, thyroxine binding protein , vitamin B12 -binding globulin , angiotensin . By β- globulins include transfer of lipids, polysaccharides and iron.Antibodies are mainly γ- globulins. Globulins are synthesized in the liver , bone marrow , spleen and lymph nodes. By day 5 grams of globulin synthesizedFibrinogen . (2-4 g / L) takes part in the formation of a blood clot . Formed exclusively in the liver.

Maintaining a constant acid-base balance of blood provided by buffer systems:

1. Bicarbonate buffer: consisting of carbonic acid and bicarbonate (salt of carbonic acid). An

excess of alkali ions to maintain the acid-base equilibrium reaction occurs.

Н2СО3 + ОН– ⇄ НСО3– + Н2О,

And with the accumulation of hydrogen ions

НСО3– + Н+ ⇄ Н2СО3

2. Phosphate buffer: is a mixture of single substituted phosphate Н2РО4

–(weak acid) and dibasic phosphate НРО42–, which has

alkaline properties Н2РО4– / НРО4

2–

An excess of alkali ions to maintain the acid-base equilibrium reaction occurs.

Н2РО4– + ОН– ⇄ НРО4

2– + Н2О,And with the accumulation of hydrogen ions

НРО42– + Н+ ⇄ Н2О4

–

3. The protein buffer: The protein buffer. It provides plasma proteins, especially albumin. These amino acids have the ability

to ionization, ie possess amphoteric properties. An excess of alkali ions to maintain the acid-base equilibrium reaction

occurs. And with the accumulation of hydrogen ions

RСООН + ОН– ⇄ RООС– + Н2О,RСОО– + Н+ ⇄ RООН 

4. Hemoglobin buffer. Essentially, there are two hemoglobin buffers - one based on reduced

hemoglobin: NNb/Nb- and the other based on oxyhemoglobin: NHbO2/HbO2. First prevails in

the venous blood, and the second - in the arterial.

An excess of alkali ions maintain the acid-base equilibrium reaction occurs:

НHb + ОН– ⇄ Нb– + Н2О;

НHbО2 + ОН– ⇄ НbО2– + Н2О,

When accumulation of hydrogen ions occurs:Нb– + Н+ ⇄ ННb;

НbО2– + Н+ ⇄ ННbО2

1. pH (from Eng. power Hydrogen - the power of hydrogen), which is equal to 7,35-7,45.2. Tension of CO2 - pCO2, which is normally 5,3-6,1 kPa (40-46 mm Hg).3. Standard bicarbonate, international designation SB (standart bikarbonate) - estimated. At standard conditions is 20-27 mg / dL.4. True, actual bicarbonate, international designation AB (actual bikarbonate), is 190-25 mg / dL.5. Excess (deficiency) framework, international designation CE (D) (base ecxess (deficit) equals ± 2,3 mmol / l.6. The sum of the bases of all the blood buffer systems, international designation BB (batter bases) is 40-60 mg / dL.

The basic amount of iron in the body (57.6%) is part of hemoglobin in red blood cells and is found.Iron enters the body in the food (meat, liver, fish, rice, peas, raisins, apricots). It is best absorbed iron, which is part of the food in the form of heme.

Hemoglobin Erythrocytes derive their colour from a complex protein called hemoglobin. This substance is composed of a pigment, heme, containing iron, and the protein glohin. Hemoglobin has the power to attract oxygen molecules and to hold them in a loose chemical combination known as oxyhemoglobin. It is said, therefore, to have a chemical affinity for oxygen.

MyoglobinHem is also part of the structure of myoglobin, an oxygen-binding pigment found in red (slow) muscles and in the respiratory enzyme cytochrome. Porphyrins other than that found in hem play a role in the pathogenesis of a number of metabolic diseases (congenital and acquired porphyria, etc.) It may be the reserve pigments, which give the tissue oxygen in a small oxygen condition.

To determine hemoglobin levels proposed many different methods:

• Gas metric method - measuring the amount of bound oxygen (1 g Hb can connect 1.36 ml of oxygen);

• Iron metric - measuring iron levels in the blood (iron content in Hb is 0.34%);

• Colorimetric - comparing the color of the solution to the color of the blood of the standard solution.