Transcript Chapter 3

Chapter 3
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BLOOD
functions of blood
1.Transportation
• O2 and CO2
• nutrients(glucose, lipids, amino acida)
• waste products(e.g. metabolites)
2. Homeostasis
• Regulation hormones
• pH(buffer pairs)
body temperature
3. Protection
• blood coagulation
• Immunity
Key points in this chapter:
1.the formation and roles of the osmotic pressure of
plasma.
2.the functions of erythrocytes and the factors that effect
the production of erythrocytes.
3.functions of leukocytes.
4.the characteristics of platelets and the functions of
platelets in the physiological hemostasis.
5.intrinsic and extrinsic pathway of blood coagulation.
6.the anticoagulative functions of antithrombin Ⅲ,
heparin.
7.fibrinolysis and diagram the fibrinolytic system
homeostasis
1.Components and Physicochemical
Properties of Blood
1.1 Components of blood
Blood
RBC
Blood cells（45％） WBC
PLT
Water（91％ of plasma ）
Inorganic constituents(1% of plasma)
Plasma
（55％）
e.g. ions:Na+, Cl-, K+, Ca2+
albumin（A）
Protein globulin（G）
fibrinogen（F）
Organic
Nutrients: glucose, amino acids,
constituents
lipids and vitamins
Waste products e.g. urea
Dissolved gases O2, CO2
Hematocrit
（红细胞比容）
The volume of red
bolld cells as a
percentage of
centrifuged whole
blood.
M:40%~60%,
F:37%~48%,
Blood Volume
Blood volume equal approximately to 7%8% of body weight.
e.g. a person weigh 70kg, then blood volume
is 4.9L, if take the hematocrit to be 45%
erythrocyte volume=0.45×4.9L=2.2L
plasma volume=4.9L-2.2L=2.7L
1.2 Physical and chemical properties of blood
1.2.1specific gravity of blood
» Depending on hematocrit and protein composition
» Whole blood:1.050-1.060
» Plasma:1.025-1.035
» Red blood cells:1.090
1.2.2.Viscosity of blood
Relative viscosity of whole blood 4-5depending on
hematocrit
Relative viscosity of plasma 1.6-2.4 related to the
protein composition of the plasma
1.2.3. Osmotic pressure of plasma
the pressure that must be applied to the
plasma to prevent the net flow of water into
the plasma is termed the osmotic pressure.
(300mmol/L=5330mmHg) （Fig.）
The osmotic pressure of a
solution depends on the
number of solute particles
in the solution, not on their
chemical composition and
size.
Osmotic pressure of plasma
Crystalloid osmotic pressure
concept: Pressure gengrated by all crystal substances,
particularly NaCl.
role：Important in maintaining fluid balance across cell
membranes
Colloid osmotic pressure
concept:pressure generated by plasma proteins,
particularly albumin
role：
Approximately
25 mmHg, but
important in fluid
transfer across
capillaries
1.2.4.Plasma pH
Normal range:
7.35-7.45
Buffer systems in blood
NaHCO3/H2CO3
Na2HPO4/NaH2PO4
Pro-Na/Pro
Hb
Lung and kidney
Fig
2. Physiology of blood cells
2.1 Red blood cells(erythrocytes)
2.1.1 Count
RBCcount
M: (4.0~5.5) ×1012/L
W: (3.8~4.6) ×1012/L
Hemoglobin concentration
M: 120~160g/L
W: 110~150g/L
2.1 Red blood cells(erythrocytes)
Morphology
Biconcave discs
Without a nucleus
2.1.2 RBC function
① transport O2、CO2
②buffering
Hb+H+=HHb
2.1.3 Production of RBC
(1)Nutritional requirements for
erythropoiesis
合成原料
Many vitamins, minerals, and proteins
iron
红细胞成熟因子
folic acid, VitB12
intrinsic factor
anemia
(2) Regulation of erythropoiesis
*erythropoietin(EPO)
*androgen 雄激素
促红细胞生成素
在哪生成
？
2.2 White blood cells (Leucocytes)
2.2.1 Types of WBC
WBC count
Count(×109/L)
%
Granulocytes
Neutrophils
Basophils
Eosinophils
2.0～7.0
0～0.1
0～0.5
50～70
0～1
1～5
Monocytes
0.1～0.8
1～8
Lymphocytes
0.8～4.0
20～40
WBC
Total
4～10
2.2.2 WBC function
1) neutrophil
① protect the body against invading
organisms
② eliminate immune complex, dead
tissues, aged RBC
piapedesis phagocytosis
游走性
2) basophil
contain granules
① release heparin (肝素)
② release histamine
组织胺
allergic reaction
3) eosinophil
① restrict allergic reaction induced by
basophil and mast cell
a. produce PGE, that inhibit active
substance released from basophil
b. engulf granules released from basophil
c. release histaminase
② antagonize parasites
4) monocyte-macrophage
① engulf invading organisms
② eliminate immune complex, dead tissues
③ recognise and kill tumour cell
④ activate lymphocyte
⑤ release cytokines
5) lymphocyte
T lymphocyte
B lymphocyte
Immune function
2.3 Platelets(thrombocytes)
• Normal value(100-300) ×109/L
• Play an important role in
hemostasis(止血）
2.3.1 Physiological properties of platelet
(1)Adhesion（粘附）
Platelets adhere to the vessel wall at the
site of injury
(2)Aggregation（聚集）
Platelets adhere to one another
纤维蛋白原或
血管血友病因子
（vWF)
Inducers of platelet aggregation
• ADP
low dose 1st reversible phase
high dose 2nd irreversible phase
• Thromboxane A2(TXA2) 血栓烷素A2
• Collagen 胶原
阿斯匹林
• Thrombin 凝血酶
(3)Release