Plasma Flashcards
How much water is in the average 70kg man?
60L
What are the proportions of water In Each compartment?
Intracellular
23L 55%
Interstitial
19L 45%
Blood plasma
3L 7%
Trans cellular fluid
1L 2%
What is the intracellular fluid?
Cytoplasm
What is the large compartment of extracellular fluid?
Interstitial fluid
Carries oxygen and nutrients to cells, and a vehicle for the removal of cellular waste products
Drained in lymphatic vessels where it is called lymph
What is the medium compartment of extrastitial fluid?
Plasma
Contains much more protein that interstitial fluid
What is the smallest compartment of extracellular fluid?
Trans cellular fluid
Includes ocular fluids and CSF
What is the simple definition of plasma?
The liquid component of blood
Around 55% of total blood volume
If you treat blood with an anticoagulant and centrifuge it what happens?
The cellular components separate from the plasma
Top: plasma 55%
Middle: buffy coat <1%
Platelets and leukocytes
Bottom: red blood cells 45%
What is apheresis?
“To take away”
Blood of a donee is removed and centrifuged to remove a particular cellular component. The remainder is returned to the donor
What can therapeutic apheresis be used to treat?
Plasma exchange
MS and myeloma
Low density lipid removal
Patients with Atherosclerosis
Red cell exchange
Sickle cell
Platelet depletion
Disorders of homeostasis
White blood cell depletion
Leukaemia
What is the difference between plasma and serum
Serum is generated by letting blood clot, depleting the plasma of clotting factors and trapping cells and platelets within the clot
Plasma is quicker to prepare but serum generates a cleaner sample
What are some of the functions of plasma?
Clotting - clotting factors and VWF are found in plasma
immune defence - antibodies and complement proteins
Osmotic pressure maintenance - proteins such as albumin help maintain colloidal osmotic pressure
Metabolism - glucose amino acids and vitamins
Endocrine - hormones
Excretion - waste products such as urea travel to the kidneys in plasma
How much of plasma is proteins?
7%
These can be assayed by electrophoresis
What are the two main types of plasma proteins?
Serum albumin and globulins
Where is serum albumin produced?
The liver
Makes up 55% of all plasma proteins
What are the key functions of serum albumin
Transport of lipids, hormones and ions
Maintaining the osmotic pressure of plasma
Transporting fatty acids around the body for use by other tissues in B-oxidation
What are the theee types of globulins in plasma?
Alpha
Beta
Gamma
Alpha globulins can be separated into Alpha-1 and alpha-2
What is the alpha-1 globulin in plasma and what does it do?
Alpha-1 antitrypsin (A1AT)
Produced by the liver
Inhibits protest enzymes. Protecting tissues form a range of enzymes, notably neutrophil elastase, released by neutrophils during inflammation
A1AT deficiency can damage the lungs leading to a loss of deficiency
What are the alpha-2 globulins In plasma?
Haptoglobin and a2-macroglobilin
Haptoglobin binds to haemoglobin releases from erythrocytes and the resulting complex is removed by the spleen
Measuring levels of haptoglobin is useful in the diagnosis of haemolytic anemia
A2-macroglobulin is a broadly active protease inhibitor which can I activate fibrinolysis
What are the beta globulins?
Includes complement proteins C3 and C4
Transferrin
Plays a role in the transport of iron
What are the gamma globulins in plasma?
Immunoglobulins (antibodies) and the acute phase protein C-reactive protein
Increased proportions of these can suggest increased immune activity, associated with infection
What is the role of electrolytes in plasma?
Although only 1%
Play a key role in osmolarity
What are the concentrations in mmol/L of the main ions in plasma?
Plasma Blood Na+ 150 5 K+ 5 140 Ca2+ 3 1e-4 Mg2+ 2 0.5
Cl- 110 10
What are the roles of intracellular calcium and magnesium ions?
Calcium-cell signalling
Magnesium-co factor for many enzymes
How is the electrolyte gradient that keeps cells alive kept in balance?
Na+-k+ pump
Active transport of ions via the sodium potassium pump
Why is the sodium potassium pump also called the sodium potassium ATPase?
The hydrolysis of ATP is required to provide the energy for transportation
How much of the ATP consumed during rest is but the sodium potassium ATPase?
1/3
How does the sodium pay assign pump work?
3 sodium out
2 potassium in
Using energy from the hydrolysis if ATP
What happens to cells when ATP is depleated?
The sodium potassium ATPase stops working, so there is an influx of Sodium ions and water. This causes cells to become more round
