Anatomy and physiology of rbcs Flashcards
What are the functions of blood
Transport
Regulation
Defence
Aspects of the blood to look at clinically include
Volume of the blood
Packed cell volume
What is PCV- packed cell volume
Tells you the proportion of the cells that make up that sample
What happens when you take blood and spin it
Separates into plasma and cellular components
What do we use to spin blood
Centrifuge
Blood is made up of
Plasma
Erythrocytes
Leukocytes
What colour is plasma
Yellow- colourless
When would plasma have a cloudy appearance
When there is a high lipid content
Why would there be a high lipid content in plasma
High levels of fat in the bloodstream
How is plasma obtained from blood
Using anticoagulant
Why is anticoagulant needed in plasma sampling
So a clot can be formed
Does plasma contain clotting factors
Yes
Does serum contain clotting factors
No
Difference between serum and plasma
Serum is the liquid you get off blood that is derived from clotting factors
In what animals is there a high concentration of albumin to globulin
Humans
Sheep
Goats
Dogs
In what mammals is there an equal concentration of albumin to globulins
Horses
Pigs
Cows
Cats
Where is albumin formed
Liver
What is albumin a source of
Amino acids
What is globulin formed by
Immune cells
Where is fibrinogen formed
Liver
What other components does plasma contain
Enzymes
Hormones
Dissolved nutrients
Waste products
Site of blood cell production in foetus
Bone marrow
Liver
Spleen
Site of blood cell production in young animal
Bone marrow
Site of blood cell production in old animal
Bone marrow
As age increases what happens to the amount of places that blood cells are produced
Decreases
Types of mature blood cells
Lymphocyte
Erythrocyte
Neutrophil
Monocyte
Eosinophil
Basophil
Platelets
What is the function of an erythrocyte
Supply oxygen
What is the structure of an erythrocyte
Biconcave disc- increased surface area
How is oxyhaemoglobin formed
Oxygen reacts with Fe in the haem
Reticulocytes are
Nucleated immature rbcs
What type of relationship does Haemoglobin and oxyhameoglobin have
Dynamic relationship
Haemoglobin shows what type of binding
Cooperative
Haemoglobin molecules can hold how many oxygen molecules
4
Affinity of Hb for O2 can be influenced by
PH
Temperature
CO2 concentration
At the start of partial pressure graph what happens
At very low partial pressure
Sharp increase
First molecule of oxygen binds then second molecule has higher affinity to bind.
Curve can shift depending on
Conditions
What factors to shift curve to the right
Low pH
High temperature
High CO2 concentration
To shift curve to left
High pH
Low temperature
Low CO2 concentration
Lungs O2 in
Loaded
Tissue 02 is
Unloads
Iron
Hb production, lost via excretion, skin sloughing, blood loss
Folic acid is needed for
Needed for DNA and RNA synthesis
Vitamin B12 is needed for
Maturation of erythrocytes and formation of DNA
What happens when erythropoietin decreased O2 delivery to kidney
Stimulates increased EPO production
What are the red cell indices
MCV- mean corpuscular volume
MCH- mean corpuscular Hb content
MCHC- mean corpuscular Hb concentration
Are there antigens on erythrocytes
Yes
Natural isoantibodies are produced
In absence of immune reaction
Immune antibodies are produced
Following exposure to foreign antigens
Humans have naturally occurring what
Isoantibodies
Horses have the blood isoantigens
A C D K P Q T U
Cattle has the blood isoantigens
A B C F-V J L M N S Z R-S
Sheep have the blood isoantigens
A B C D M R-O X-Z
What breed has naturally occurring isoantibodies
Cat
Cats have what blood group
A B AB
Type B cats have what type of anti antibodies
A
Haemostasis is
Spontaneous arrest of bleeding from a ruptured vessel
What are the three main physiological processes in haemostasis
Vascular response
Platelet plug formation
Coagulation to form a clot
Vascular response process
Damage to endothelium causes constriction of smooth muscle wall.
Maintained by substances released from endothelium and platelets.
Platelet plug formation process
Platelet will move out of blood vessel and into the wound to make contact with collagen.
When they make contact with collagen they become activated and this causes a conformational change in platelets.
Actin and myosin in platelets cause smooth muscle to contract.
Platelet plug formation from when the smooth muscle contracts process
After smooth muscle contracts tbis causes cells to contract then this releases secretory vesicles which contain enzymes
What enzymes are in the vesicles in platelet plug formation
Arachadonic acid which enters the blood stream to form thromboxane A
What happens to the activated platelets
Sticky and attaches to von Willebrand factor
What is von Willebrand
Protein which sets on endothelium wall
The thromboxine A causes
Activation of platelets
When other platelets pass by what happens
They stick together and form a plug
In healthy tissue what acts on arachondic acid
Prostacyclin
What does arachondic acid and prostacyclin combine to make
Prostagland I which means not all platelets are aggrevated
Coagulation is
Complex series of reactions
Prothrombin gets turned into
Thrombin
Thrombin gets turned into
Inactive factor XIII which gets activated
Active factor xiii gets converted to
Stabilised fibrin
Thrombin gets converted to
Fibrinogen to loose fibrin
What does stabilised fibrin do
Clots the blood linked together to trap rbcs
Calcium is required because
Blood wont clot
Anti clotting mechanism
PG12 inhibits platelet aggression
Dissolution of a blood clot depends on two processes
Clot retraction
Fibrinolysis
Urokinase is
Tissue type plasmiogen activator, activated by kalikrien or plasmin but does not bind to fibrin
Dissolution of a blood clot is a
Self limiting system
Anti clotting drugs/ agents
Aspirin
Coumarin derivatives
K dependent clotting factors
Heparin
Calcium chelating agents
Aspirin what does it do
Inhibits COX and thus inhibits thrombotane A2 production thus reduced platelet aggregation and coagulation
Coumarin derivative what does it do
Affects production of vitamin K dependent clotting factors within the liver
Heparin what does it do
Natural cofactor of anti thrombin III
What is bleeding time
Time to form primary plug after stab or incision. Screening test for vascular and platelet disorders
Whole blood clotting time what is it
Time taken for 1ml of blood to clot
One stage prothrombin test what is it
Plasma incubated with tissue thromboplastin and clotting initiated by the addition of calcium
Activated partial prothrombin test
Plasma is activated under controlled conditions in the presence of phospholipid and clotting is activated by calcium
Von Willebrand disease is the most common bleeding disorder in
Dogs
What breeds is Von Willebrand common in
Doberman
Scottish terrier
Shetland
Sheepdog
What is transmitted as a autosomal trait
Von Willebrands disease
Haemophilia is a
Factor XIII deficiency
Haemophilia doesn’t have a
Normal clotting disease
What breed is haemophilia common in
German Shepard
Haemophilia is a what type of condition
Sex linked recessive
Clinical signs of haemophilia seen in early life
Excessive bleeding
Haematoma
Internal bleeding
Death
Haemophilia is what type of factor deficiency
Factor IX
Factor IX deficiency is Most common in what breeds
Cairn terriers, German wire haired terriers, st Bernard’s, coon hounds, Scottish terriers, old English sheepdogs
Factor IX deficiency is less common than
Factor XIII
