PHYSIOLOGY OF THE BLOOD
TOTAL BODY WATER
Males: 60 %
Females: 50 %
Extracellular fluid (ECF) – 20 %, 14 litres
1) intravascular (blood-plasma 5%, lymph)
2) extravascular – intersticial 15 %
Intracellular fluid (ICF) – 40 %, 28 l
BLOOD VOLUME
Adults: 7% of b.w.
- Males: 7.7 % b.w., 5.5 l; 70 ml/kg
- Females: 6.5-7 % (more fat)
Normovolemia
Hypovolemia:
- proportional
- hemoconcentration
- hemodilution
Hypervolemia
Measurement – methods: direct and indirect (radioisotopes, dyes)
BIOPHYSICAL CHARACTERISTICS OF THE BLOOD
1) Specific gravity
Blood - 1056 (152-1063) kg/m3
- plasma 1027
- red blood cells 1090
2) Viscosity
- water = 1; blood 4-5.4x more
Syndrome of hyperviscosity – impairment of microcirculation, hypoxia,...
3) Hematocrit
- the percentage of red blood cells in the whole blood
Males: 0.44±0.05 (44±5 %)
Females: 0.39±0.04 (39±4 %)
Newborns: 50-60 %
1
, ERYTHROCYTE SEDIMENTATION RATE (ESR)
Blood - suspension ⇒ electrical bilayer: RBC – negative charges
plasma proteins – positive charges
Factors influencing ESR
1) Plasma proteins
2) RBC count and size
3) Lipidemia
4) pH of plasma
Values: M: 2-5 mm/h
F: 3-8 mm/h (less RBC, more fibrinogen)
Determination: Fahraeus-Westergreen method (FW) - see practicals
Acceleration of ESR: physiological (gravidity, menstruation)
pathological (infect.diseases, tumors, liver diseases,...)
RED BLOOD CELLS (RBC)
- non-nucleated cells
- biconcave discs, diameter 7.2 µm, thickness 2.1 µm, volume 85 fl, surface 130 µm2;
surface of all RBC 50x60 m
RBC count
M: 4.3 – 5.3 x 1012/l
F: 3.8 – 4.8 x 1012/l
Newborns: 7-8 x 1012/l
Hypererythrocytosis (polycytemia, polyglobulia) ↑ count
– physical activity, high altitude, hemoconcentration
Erythrocytopenia (anemia) ↓ cout: physiol.(sucklings), pathologic
Structure
- water –70% and dry subst.30%
membrane, stroma, hemoglobin
membrane: lipid bilayer with proteins (peripheral, integrat.)
other substances: hemoglobin, ions (K, Na, Ca), enzymes (40), glutathion, ...
Metabolism: RBCs have low metabolic needs
1) Embden-Mayerhof pathway (anaerobic - 90 %)
2) Hexose-monophosphate shunt (aerobic - 10%)
HEMOGLOBIN
Molecular structure: tetramer
M.W.: 64 kDa
2
, Heme: ferrous protoporphyrin (Fe2+)
Globin: 4 polypeptide chains (HbA: 2 alpha + 2 beta)
Quantity of Hb
M: 135-170 g/l
F: 120-160 g/l
Newborns: 190, sucklings:110
Each gram of Hb can carry 1.34 ml O2 ⇒ one litre of blood cca 200 ml O2
Measurement of Hb concentration: spectrophotometry – see practicals
Hemoglobin derivates
Physiological
1) OxyHb (+O2)
2) DeoxyHb (-O2)
3) CarbaminoHb (+CO2)
Pathological
1) CarboxyHb (+CO)
2) MetHb (+OH): Fe2+→ Fe3+
Types of hemoglobin
1) Embryonic
a) Gower I (2 zeta, 2 epsilon)
b) Gower II (2 alpha, 2 epsilon)
c) Portland (2 zeta, 2 gamma)
2) Fetal (2 alpha, 2 gamma)
3) Adult
a) HbA (2 alpha, 2 beta)
b) HbA2 – minor component (2 alpha, 2 delta) – up to 2 % - in adults
HEMOLYSIS
Destruction of the RBC membrane and release of Hb
1) Osmotic (hypotonic, hypertonic)
2) Physical (temperature, mechanical, radiation)
3) Chemical (saponin-see practicals)
4) Toxic (cobra venom – hemolysis)
5) Immunologic (mismatched transfusion)
6) Hereditary (deficiency of G-6PD)
3
TOTAL BODY WATER
Males: 60 %
Females: 50 %
Extracellular fluid (ECF) – 20 %, 14 litres
1) intravascular (blood-plasma 5%, lymph)
2) extravascular – intersticial 15 %
Intracellular fluid (ICF) – 40 %, 28 l
BLOOD VOLUME
Adults: 7% of b.w.
- Males: 7.7 % b.w., 5.5 l; 70 ml/kg
- Females: 6.5-7 % (more fat)
Normovolemia
Hypovolemia:
- proportional
- hemoconcentration
- hemodilution
Hypervolemia
Measurement – methods: direct and indirect (radioisotopes, dyes)
BIOPHYSICAL CHARACTERISTICS OF THE BLOOD
1) Specific gravity
Blood - 1056 (152-1063) kg/m3
- plasma 1027
- red blood cells 1090
2) Viscosity
- water = 1; blood 4-5.4x more
Syndrome of hyperviscosity – impairment of microcirculation, hypoxia,...
3) Hematocrit
- the percentage of red blood cells in the whole blood
Males: 0.44±0.05 (44±5 %)
Females: 0.39±0.04 (39±4 %)
Newborns: 50-60 %
1
, ERYTHROCYTE SEDIMENTATION RATE (ESR)
Blood - suspension ⇒ electrical bilayer: RBC – negative charges
plasma proteins – positive charges
Factors influencing ESR
1) Plasma proteins
2) RBC count and size
3) Lipidemia
4) pH of plasma
Values: M: 2-5 mm/h
F: 3-8 mm/h (less RBC, more fibrinogen)
Determination: Fahraeus-Westergreen method (FW) - see practicals
Acceleration of ESR: physiological (gravidity, menstruation)
pathological (infect.diseases, tumors, liver diseases,...)
RED BLOOD CELLS (RBC)
- non-nucleated cells
- biconcave discs, diameter 7.2 µm, thickness 2.1 µm, volume 85 fl, surface 130 µm2;
surface of all RBC 50x60 m
RBC count
M: 4.3 – 5.3 x 1012/l
F: 3.8 – 4.8 x 1012/l
Newborns: 7-8 x 1012/l
Hypererythrocytosis (polycytemia, polyglobulia) ↑ count
– physical activity, high altitude, hemoconcentration
Erythrocytopenia (anemia) ↓ cout: physiol.(sucklings), pathologic
Structure
- water –70% and dry subst.30%
membrane, stroma, hemoglobin
membrane: lipid bilayer with proteins (peripheral, integrat.)
other substances: hemoglobin, ions (K, Na, Ca), enzymes (40), glutathion, ...
Metabolism: RBCs have low metabolic needs
1) Embden-Mayerhof pathway (anaerobic - 90 %)
2) Hexose-monophosphate shunt (aerobic - 10%)
HEMOGLOBIN
Molecular structure: tetramer
M.W.: 64 kDa
2
, Heme: ferrous protoporphyrin (Fe2+)
Globin: 4 polypeptide chains (HbA: 2 alpha + 2 beta)
Quantity of Hb
M: 135-170 g/l
F: 120-160 g/l
Newborns: 190, sucklings:110
Each gram of Hb can carry 1.34 ml O2 ⇒ one litre of blood cca 200 ml O2
Measurement of Hb concentration: spectrophotometry – see practicals
Hemoglobin derivates
Physiological
1) OxyHb (+O2)
2) DeoxyHb (-O2)
3) CarbaminoHb (+CO2)
Pathological
1) CarboxyHb (+CO)
2) MetHb (+OH): Fe2+→ Fe3+
Types of hemoglobin
1) Embryonic
a) Gower I (2 zeta, 2 epsilon)
b) Gower II (2 alpha, 2 epsilon)
c) Portland (2 zeta, 2 gamma)
2) Fetal (2 alpha, 2 gamma)
3) Adult
a) HbA (2 alpha, 2 beta)
b) HbA2 – minor component (2 alpha, 2 delta) – up to 2 % - in adults
HEMOLYSIS
Destruction of the RBC membrane and release of Hb
1) Osmotic (hypotonic, hypertonic)
2) Physical (temperature, mechanical, radiation)
3) Chemical (saponin-see practicals)
4) Toxic (cobra venom – hemolysis)
5) Immunologic (mismatched transfusion)
6) Hereditary (deficiency of G-6PD)
3
