The cardiovascular system consists of the heart, blood vessels (including arteries, capillaries and veins) and blood.

(1) heart

1, the position and shape of the heart

The heart is a hollow fibrous organ, which is inverted cone-shaped, slightly flat from front to back, surrounded by pericardium, and obliquely located in the middle mediastinum of the chest, about 2/3 to the left of the midline and 1/3 to the right of the midline. Facing the sternum and the front of the second to sixth costal cartilage; Posterior plane of thoracic vertebrae 5~8; Bilateral adjacent pleural cavity and lung; The upper part is connected with the great blood vessels entering and leaving the heart; Under the diaphragm. The long axis of the heart inclines from the right shoulder to the left subcostal region, making an angle of 45 degrees with the body midline. The bottom of the heart is fixed by the root of the great vessels entering and leaving the heart and the folded edge of the pericardium, while the ventricular part is more active.

2, the structure of the heart cavity

The heart cavity is divided into two halves by longitudinal interatrial septum and interventricular septum, which are not connected with each other. Each half is divided into upper atrium and lower ventricle, and the atrium and ventricle on the same side are connected through the atrioventricular orifice.

3, the structure of the heart wall

The heart wall consists of epicardium, myocardium and endocardium.

4. Blood vessels of the heart

5, the conduction system and innervation of the heart

6, pericardium

(2) Blood vessels

1, type and distribution of blood vessels

2. Blood vessels of pulmonary circulation

3. Blood vessels of systemic circulation

(1) Arterial system of systemic circulation

⑵ Systemic venous system

(3) Characteristics of fetal blood circulation

Second, the lymphatic system

The lymphatic system consists of lymphatic vessels, lymphoid tissues, lymphoid organs and lymph.

(1) lymphatic vessels

Lymphatic vessels are the channels through which lymph passes. According to the collection order, caliber and wall thickness, it can be divided into capillary lymphatic vessels, lymphatic vessels, lymphatic trunks and lymphatic vessels.

1, lymphatic capillaries

2. Lymphatic vessels

3. Lymphatic trunk

4, lymphatic catheter

5. Lymphogenesis and lymphatic circulation

(2) Lymphatic tissues and organs

1, lymphoid tissue

2. Lymphatic organs

(1) thymus

⑵ Spleen

⑶ Tonsils

(4) Blood lymph nodes

5] Lymph nodes

Microanatomy of vascular science

First, the cardiovascular system

(1) blood vessels

1, capillary

(1) structure

(2) Classification

① Continuous capillary

② Perforated capillaries

③ Blood sinus

2. Arteries

3. Veins

(2) Heart

1, endocardium

2, myocardial membrane

3, epicardium

4. Heart valve

(3) Microcirculation

Blood circulation in microvessels between arterioles and venules.

1, structure

2, the way

Second, the lymphatic system

(1) thymus

1, cortex

2. Medulla

3. Blood thymus barrier

(2) Lymph nodes

1, cortex

2. Medulla

(3) Spleen

1, capsule and trabecular meshwork

2. Essence

(1) white pulp

(2) Red pulp

Cyclic physiology

First of all, the pumping function of the heart

(1) cardiac cycle

Every time the heart contracts and relaxes, it is called a cardiac cycle.

Generally, the process of cardiac cycle is divided into

1, atrial contraction

2. Ventricular contraction

3. Ventricular diastolic period

(2) Heart rate

The number of heartbeats per minute is called heart rate.

(3) Heart sound

(D) Cardiac output and its influencing factors

1, output per stroke and output per minute

Stroke output = ventricular end diastolic volume-ventricular end systolic volume

Output per minute = heart rate × stroke output

2. Main factors affecting cardiac output

(1) venous reflux

⑵ Ventricular contraction force

⑶ Heart rate

Second, the bioelectric phenomenon and physiological characteristics of myocardium

Types of myocardial cells:

A, working cells: constitute the atrial and ventricular walls.

Excitement, conduction, contraction, but not self-discipline.

B, special myocardial cells: the special conduction system of the heart, with excitability, conductivity, self-discipline, almost no contraction function.

(A) the bioelectric phenomenon of myocardial cells

1, transmembrane potential of working cells and its formation mechanism

⑴ resting transmembrane potential: at rest, both sides of the membrane are polarized, and the membrane is -90mv.

⑵ Action potential: Compared with skeletal muscle, the action potential of ventricular muscle is much more complicated and lasts longer during repolarization, and it is asymmetric with ascending branch. Generally, it is 0, 1, 2, 3, 4 and other numbers. Used to indicate the various periods of myocardial action potential.

① Depolarization process (0 phase)

② repolarization 1 phase:

③ second phase repolarization platform

④ Late stage of rapid repolarization (phase 3)

⑤ Rest period (4 cycles)

(2) Electrophysiological characteristics of myocardium

All myocardial cells are excitable.

1, the factors that determine and influence excitability:

_ _ _ ① Resting potential level

_ _ _ ② Threshold potential level

_ _ _ ③ Characteristics of sodium ion channel: There are three states of sodium ion channel: activation, deactivation and standby.

2. Periodic changes of excitability of myocardial cells after one excitation:

_ _ _ ① Effective refractory period

_ _ _ ② Relative refractory period

_ _ _ (3) Extraordinary period

3. The relationship between the periodic change of excitability and the contraction activity during the excitement:

(1) tension contraction does not occur.

(2) Functional compatibility

(3) Premature beats and compensatory intervals

(3) Automatic rhythm of myocardium

The characteristic that tissues and cells can automatically generate rhythmic excitement without external stimulation is called autonomy. The self-discipline of myocardium comes from myocardial cells themselves. An autonomous tissue or cell is called an autonomous tissue or an autonomous cell.

(4) conduction of myocardial conductivity and cardiac excitability _ _

Third, vascular physiology.

(1) Blood flow, blood flow resistance and blood pressure

1, the formation of blood pressure and its influencing factors

Blood pressure refers to the lateral pressure of blood in blood vessels on the unit area of blood vessel wall, that is, pressure. The unit of blood pressure is kilopascals.

(1) Formation of blood pressure

① The filling of blood to blood vessels and the average filling pressure of circulatory system: Only when blood fills blood vessels can we talk about the lateral pressure on blood vessel walls.

② Cardiac ejection: The energy released during ventricular contraction is divided into two parts.

___A, used to promote blood flow, is kinetic energy,

___B, which forms lateral pressure on the blood vessel wall, is potential energy.

③ Peripheral resistance

⑵ Factors affecting arterial pressure

All factors that can affect cardiac output and peripheral resistance can affect arterial blood pressure.

① Cardiac output per stroke

② Heart rate

③ Peripheral resistance

(4) Elastic reserve of artery and aorta.

⑤ Ratio of circulating blood volume to vascular system capacity

2. Blood pressure and pulse pressure

When the ventricle contracts, the arterial pressure rises to the highest value, which is called systolic pressure; When the ventricle relaxes, the blood pressure drops to the lowest value, which is called diastolic pressure; The difference between systolic and diastolic blood pressure is called pulse pressure.

(2) Formation of interstitial fluid and its influencing factors

Effective filtration pressure = (capillary pressure+tissue colloid osmotic pressure)-(plasma colloid osmotic pressure+tissue static pressure).

When the effective filtration pressure is greater than 0, the interstitial fluid is generated, otherwise the interstitial fluid is reabsorbed.

(3) the production of lymph

Part of the tissue fluid left in the tissue returns to lymphatic vessels to form lymph.

1, the physiological significance of lymphatic reflux

① protein molecules in tissue fluid can be brought back to the blood.

② Remove larger molecules in tissue fluid that can not be reabsorbed by capillaries, as well as red blood cells and bacteria in tissues,

③ It plays an important role in the absorption of nutrients, especially fat.

④ It plays a certain role in the formation and reabsorption balance of interstitial fluid.

2. Factors affecting lymphogenesis:

Fourthly, the regulation of cardiovascular activities.

neuroregulation

1, the nerve branch of the heart

2. Nerve control of blood vessels

3. Cardiovascular center

4. Cardiovascular reflex

(1) carotid sinus and aortic arch pressure reflex-decompression reflex

⑵ Drug sensitivity reflex of carotid body and main vein body.

(2) Body fluid regulation

1, renin-angiotensin system

2, vasopressin (antidiuretic)

3, adrenaline, norepinephrine

4. Vasoactive substances produced by vascular endothelium

blood

First, the internal environment of the body.

The liquid contained in animals is always called body fluid.

Single-celled organisms live in water and can directly exchange materials with the water environment. Most cells of multicellular organisms cannot directly contact with the water environment of the external environment, and can only be indirectly exchanged with water (or external environment) through extracellular fluid. Therefore, extracellular fluid constitutes the direct environment of cell life, which is called internal environment to distinguish the external environment of the whole organism.

Second, the composition and physical and chemical characteristics of blood

1, blood components

2. Physical and chemical characteristics of blood

(1) Color and smell of blood

(2) the density of blood

(3) Blood viscosity

(4) Osmotic pressure of blood

Osmotic pressure refers to the force of solute in solution to promote water molecules to diffuse from one solution to another through semi-permeable membrane.

Plasma osmotic pressure includes crystal osmotic pressure and plasma colloid osmotic pressure. Plasma osmotic pressure formed by crystalline substances (such as electrolytes) in plasma is mainly called crystalline osmotic pressure, which is extremely important for maintaining water balance inside and outside cells. The osmotic pressure formed by plasma protein is called colloid osmotic pressure, which plays an important role in water balance inside and outside blood vessels.

5] pH value

Animal blood is weakly alkaline. Under normal circumstances, in addition to eliminating excessive acid and alkali substances through the lungs and kidneys, it mainly depends on the buffer pairs in the blood, of which the most important buffer pair is NaHCO3/H2CO3, and the content of NaHCO3 in the blood is called alkali storage.

Third, blood cell physiology.

1, erythrocyte

(1) plasticity

Red blood cells will deform when they pass through smaller blood vessels, and then return to their original state after passing through them.

⑵ Stability of erythrocyte suspension

The characteristic that red blood cells can remain suspended in plasma without sinking is called the suspension stability of red blood cells. At the end of 1 hour, the sinking distance in the erythrocyte sedimentation tube indicates the erythrocyte sedimentation rate, which is referred to as erythrocyte sedimentation rate for short.

(3) osmotic fragility of red blood cells

The rupture of red blood cells due to physical reasons is called mechanical brittleness. When the concentration of NaCl is further reduced, some red blood cells will swell and rupture excessively, releasing hemoglobin. This phenomenon is called hemolysis. The characteristics of erythrocyte swelling, rupture and hemolysis in hypotonic solution are called osmotic brittleness. The function of hemoglobin can only be played in intact red blood cells.

0.85%-0.9% NaCl is isotonic solution and isotonic solution.

2. Physiological function of white blood cells

3. Platelets

⑴ Physiological characteristics of platelets

I. Adhesion

When vascular endothelium is damaged and collagen tissue is exposed, platelet adhesion is immediately caused, which is called platelet adhesion.

B, assemble

Platelets adhere to each other and aggregate into a group, which is called platelet aggregation.

C, contraction

Refers to the contraction process of contractile protein in platelets, which can lead to blood clot retraction and thrombosis, which is beneficial to hemostasis.

D, adsorption

Platelets can adsorb various coagulation factors in plasma on the surface.

⑵ Physiological function of platelets

Mainly involved in physiological hemostasis and coagulation process.

Fourth, physiological hemostasis.

(1) Physiological hemostasis

Blood flows out of the blood vessels. Under normal circumstances, the bleeding will stop automatically after a few minutes, which is called physiological hemostasis.

Physiological hemostasis process includes three processes:

_ _ _ (1) Small blood vessels contract immediately after injury.

_ _ _ (2) Thrombosis, to achieve the initial hemostasis.

(3) Formation of fibrin block

(2) Blood coagulation

1, concept

When blood leaves a blood vessel, it changes from a sol state to an immobile gel state, which is called blood coagulation.

2. The coagulation process can be divided into three steps.

In the first stage, coagulation factor FX is activated to FXa, forming prothrombinase complex (prothrombin activator);

The second stage is the activation of prothrombin (F Ⅱ) into thrombin (F Ⅱ A);

The third stage is the transformation of fibrinogen (F Ⅰ) into fibrin (F Ⅰ A).

3. There are two ways to trigger blood coagulation.

① Coagulation of thromboplastin formed by coagulation factors in plasma is called endogenous activation pathway.

② Coagulation factor is activated by tissue factor released from extravascular tissue, which is called exogenous activation pathway.

(3) Anticoagulation and acceleration measures

1, anticoagulation measures

(1) removes calcium ions from the blood.

② Low temperature delayed snow condensation.

Smooth surface: can reduce platelet aggregation and disintegration, weaken the trigger of coagulation process, thus delaying the formation of thrombin.

④ Heparin and dicoumarin were used.

⑤ Stir

2. Accelerated measures

①Ca2+ promotes blood coagulation.

② Vitamin K promotes blood coagulation.

③ heating