名校生理学血液循环

血流通过毛细血管从小动脉到小静脉，完成 血液和组织液的物质交换。
Precapillary sphincter 毛细血管前括约肌
Function: Control of inflow of capillaries 作用：控制毛细血管的流入量。
A-V shunt (anastomosis) 动静脉短路（吻合） Function：Blood flows directly from arteriole to
血压降落与血流阻力成正比，在血流阻力最大的 微动脉段，血压降落最为显著。
Vibration 有振动
Sound 有声音
Wasteful energy more 耗能多
Poiseulle’s law for laminar flow conforms to laminar flow but turbulent flow.Under turbulent flow, the blood flow is not in direct proportion to the bp of the two ends of vessels, however to its square root.
Lowest at 2 to 3 o’clock in the morning 凌晨2 ~ 3时最低
One Peak during 6 to 10 in the morning 上午6 ~ 10时高
Another peak during 4 to 8 in the afternoon 下午4 ~ 8时高
kinetic energy： push the blood to flow
potential energy: vessel wall expand
Cardiac relaxation：large artery elasticity recovery Percentage potential energy kinetic energy : Push blood to continuously flow forward
R Q ：blood flow（血流量）
P1-P2：the dp of the two vessels ends (血管两端压力差)
R: resistance of blood flow (血流阻力)
B. Poiseulle’s law for laminar flow
Δp
πΔpr4
F = ———— = ————
层流
NR>2000 turbulent flow
湍流
Laminar flow 层流
The same flow direction 流动方向一致
no vibration 无振动
no sound 无声音
Wasteful energy less 耗能少
Turbulent flow 湍流
The different flow direction 流动方向不一致
Empirical equation（经验公式） Reynold’s number---Reynold数:
NR =ρDV/η
ρ(rho): density of fluid 液体密度 D: diameter of the tube 管径 V: velocity of flow 流速
NR< 2000 laminar flow
舒张压 （mmHg)
＜90 80 ~ 89 90 ~ 99 ≥100
C. Pressure of different vessels of systemic circulation 体循环不同血管的血压
主动脉 动脉（3mm） 微动脉起始端 微动脉末端 毛细血管起始端
平均压（mmHg）
100 95 85 55 30
泊肃叶定律适于层流情况。在湍流情况下， 泊肃叶定律不再适用，血流量不是与血管两 端的压力差成正比，而是与压力差的平方根 成正比。
2. Resistance to blood flow: 血流阻力
P1-P2 F = ———
R
8ηL R = ———
πr4
Resistance comes from external friction
静脉
容量血管
Ⅰ. Functional properties of different blood vessels 不同血管的功能特征
1. Artery: 动脉
A. Aorta and large artery (windkessel vessel ) 主动脉和大动脉，又称弹性贮器血管
pressure reservoir 压力储存器 maintain the continual blood fluid in the artery system. 维持动脉系统内连续的血流
Normal value
mmHg
kPa
100～120 13.3～16
60～80
8～10
30～40 100
4.0～5.3 13.3
MAP = DP + 1/3 (pulse P)
A. D n fluctuating rules of blood pressure 血压的昼夜波动
Double peaks and double valley (day rhythm) 双峰双谷（日节律）
Lowing down after 8 o’clock in the evening 晚上8时缓慢下降
B. Diagnosis criteria of hypertension 高血压的诊断标准
Catalogues
SP
DP
Normal prophase 1st phase 2nd phase
＜120 120～139 140～159
1. Blood flow: Blood volume passing a given section in the cardiovascular system per unit time (ml/s). 血流量：单位时间流过血管某一横截面的 血量（ml/s）。
P1-P2 A. Q = ————
CHAPTER 4 CIRCULATI 血液循环
Prof. Wang Ting huai Department of Physiology
SECTION 3 VASCULAR PHYSIOLOGY
血管生理
动脉
弹性储器血管：主动脉和大动脉 分配血管：中等动脉 阻力血管：小动脉和微动脉
毛细血管 交换血管
Low resistance vessel 低阻力血管 transport blood to every apparatus of the globle body 运送血液到全身各个器官
B. Middle artery: carry blood to arterioles (distribution vessel)
Fall of blood pressure is in direct proportion to the resistance of blood flow,and the BP decreases significantly in the arteriole ,where the blood flow resistence is the biggest.
veinule through A-V shunt . 作用：血液通过动静脉吻合由微动脉直接到达微静脉。
3. Venous Vessels ( capacitance vessel) 静脉血管（容量血管）
Large vein，vena cava，venule，veinule 大静脉，腔静脉，小静脉，微静脉
一个器官血流量的多少主要受平均动脉压和血管半径的 影响。小动脉和微动脉口径的变化是调节器官血流量和 器官之间血液重新分配的最主要因素。
3. Blood pressure 血压 4. Two requirements for blood pressure formation:
血压形成的两个条件： A. Blood filling in cardiovascular system
2. Capillary vessels: exchange vessels 毛细血管：交换血管
Blood flow from arteriole to venules by passing capillary to carry out the exchange of substances between blood and interstitial fluid.
心脏收缩 释放能量
动能：推动血液流动 势能：血管壁扩张
心脏舒张：大动脉弹性回缩 部分势能 动能：推动血液继续向前流动
Ⅲ. Arterial Blood Pressure 动脉血压 1. Normal value 正常值
Systolic Pressure 收缩压 Diastolic Pressure 舒张压 Pulse Pressure 脉压 MAP 平均动脉压
阻力
8ηL
L :血管长度
η ：血液黏度
r veinule：血管半径
The mode of blood flowing in the blood vessels can be classified iቤተ መጻሕፍቲ ባይዱto Laminar flow and turbulent flow. 血液在血管内的流动方式可以分为层流和湍流。
心血管系统血液充盈 Mean circulatory filling pressure ∽
blood volume ——————— = 7mmHg vascular volume
血液容量 循环系统平均充盈压 ————— = 7mmHg
血管容量
B. Cardiac ejection 心脏射血
Cardiac Contraction Energesis