Lecture notes on Body Fluids (HUB2019F)

Body Fluids
BODY FLUIDS................................................................................................................................................ 1
BLOOD.......................................................................................................................................................... 2
BLOOD TYPES:.........................................................................................................................................................2
Discovery:........................................................................................................................................................2
ANTIGENS & ANTIBODIES..........................................................................................................................................2
Antibody Structure:.........................................................................................................................................2
The Rh Antigen:...............................................................................................................................................3
FLUID COMPARTMENTS................................................................................................................................ 3
MEASUREMENT OF FLUID COMPARTMENT VOLUMES......................................................................................................3
Properties of a good tracer:............................................................................................................................4
Specific tracers for different compartments:..................................................................................................4
FLUID BALANCE............................................................................................................................................. 4
WATER BALANCE.....................................................................................................................................................4
Regulation of Water Gain:..............................................................................................................................5
Regulation of Water and Salt Loss:.................................................................................................................5
OSMOTIC COMPOSITION OF FLUID COMPARTMENTS.......................................................................................................5
ELECTROLYTE CONCENTRATION OF BODY FLUIDS............................................................................................................7
OSMOSIS................................................................................................................................................................7
Osmotic Pressure:...........................................................................................................................................7
Gibbs-Donnan membrane equilibrium:..........................................................................................................8
MOVEMENT OF WATER WITHIN ECF: BETWEEN PLASMA AND ISF.....................................................................................8
Lymphatic drainage:.......................................................................................................................................8
PROTEIN DEFICIENCY/MALNUTRITION (KWASHIORKOR)...................................................................................................8
CONGESTIVE HEART FAILURE.......................................................................................................................................8
HAEMORRHAGIC SHOCK............................................................................................................................................9
REGULATION OF BODY FLUID OSMOLALITY..................................................................................................................10
Control of hyper-osmolality:.........................................................................................................................10
Concentration of urine in hyper-osmolality:.................................................................................................11
Control of hypo-osmolality:..........................................................................................................................11
RAAS SYSTEMS EFFECT ON WATER AND SALT..............................................................................................................11




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, Body Fluids
Blood
Blood Types:
- 32 human blood group systems recognized
- Most important = ABO and RH systems
- Shared by apes, chimps, bonobos, gorillas
- Inherited in non-mendelian genetics (except for Rh)
- Differentiated by antigens on the cell surface:
o Type O (ii): No antigen added
 Universal donor
o Type A (iIA; IAIA): N-acetylgalactosamine added at antigen terminus
o Type B (iIB; IBIB): Galactose added at antigen terminus
o Type AB (IAIB): Both “” added at antigen terminus
 Universal recipient
- 3 alleles:
o i – codes for no antigens
o IA – codes for N-acetylgalactosamine
o IB – codes for Galactose

Discovery:
o 1900 by Dr. Karl Landsteiner at University of Vienna
o He wondered why some patients died as result of blood transfusions and others did
not


Antigens & Antibodies
- Antigens you have on your blood cells are recognized by immune system as SELF
antigens
- If foreign antigens discovered in body, antibodies (immunoglobulins) will be made by
B-cells of immune system
- Agglutination = blood clumping resulting from when antibody attacks foreign
antigen.
- Type A – anti-B antibodies
- Type B – anti-A antibodies
- Type AB – No antibodies
- Type O – anti-A & anti-B antibodies

Antibody Structure:

- Paratope (lock) of antibody fits exactly to
epitope (key) of antigen




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