Cardiovascular System II Flashcards
Rediculocytes
- Maturation ito red blood cells 3 day life span
- then RBC survives for 120days
Regulation of erythropoiesis
- Negative feedback the kidney becomes hyptoxic (O2 drops in renal artery)
- Stimulated release of erythropoetin (EPO) then stimulates bone marrow to produce erythrocytes
- New potential to carry oxygen by red blood cells
What is Hypoxia
- Haemorrage or injury
- iron deficincy
- High altitude or lung disease
How do males have more blood Red blood cells than females?
- Higher Testesterone enhances EPO production
- High EPO therefore Erythrocytes mature faster
- Increase haematocrit, dehydration and blood viscosity
- Able to transport more oxygen for respiration
Importance of Iron in blood
- 65% in Hb
- Bound with protein and stored as ferritin and haemosiderin
- Transported by binding with transferrin
How does Heam degrade?
Degraded to bilirubin, yellow pigment-Liver secretes bilirubin in bile (in intestine)-urobilinogen-stercoblin, brown pigment excreted in faeces
How does the globin degrade?
metabolised into aminoacids & recycled
Anaemia symptoms
- Fatigue
- Pallor
- Dyspnoea & chills
Haemorrhagic
- Acute or Chronic blood loss
- Treatment blood transfusion
Iron deficiency
RBC turning microcytes lacking Iron-Hb production. Treat or manage with Iron supplements
Renal treatment
lack of EPO supplement with synthetic EPO
Pernicious
- Autoimmune condition-destroy B12 absorption; without B12 RBC cannot divide or become macrocytes
- Dietry supplement of B12
Aplastic
Injury to Red Bone Marrow/ Drugs: Chemotherapy, Radiation, chemicals
Thalassemia
- Globin chain in Hb is absent or malfunction
-RBC become thin, delicate and lack Hb
-Mild to Severe subtypes- Blood transfusions
-Predominantly in Mediterranean ethnics
Sickle cell anaemia
- Mutation in Hb: one amino acid is wrong in the globin B chain (6th AA- Glutamic acid in normal RBC whereas 6th AA is Valine in sickle RBC)
- Creasent shaped :
- O2 levels are lower
- Crescent shape block flow in the blood vessels and leads to stroke and other vascular diseases
- predominently in African ethnics
Polycythaemia (too many RBC)
- Too thick too many cells increase the viscosity
- Stroke
-Coronary artery disease
-Renal disease
Stages of Haemostasis
1) Vascular spasm
2) Platelet Activation- Plug
3) Coagulation- Patch
Haemostasis
Vascular Spasm
- Pain reflux so constriction of vascular smooth muscle
- Trigger clotting chemicals/factors needed & directed to site of injury
Haemostasis
Platelet Activation- Plug
- Endothelial Damage so Collagen exposed
- Platelets stick to exposed collagen is activated
- Platelets stimulate ADP, Thromboxane A2 and Serotonin
- Von Willebrand Factor- Stabilise collagen-platelet adhesion
- Positive feedback - more platelet release
Haemostasis
Coagulation- Patch
- Clotting factors (procoagulants) in Liver
Vitamin K, the biosynthesis clotting factors
Plasma proteins I to XIII - Happens while platelet activation occours
X-A prothromin Activator
- Intrinsic (blood) and extrinsic activates (tissue level) to x Prothrombin
- Converted into Thrombin (can go straight to fibrin mesh
- Fibrinogen (soluble)
- Fibrin (insoluable)
- Fibrin mesh
i
Clot retraction countercurrent with vessel
- Actin and myosin in platelet contracts pulls fibrin
- Platelet-derived growth factor which stimulates smooth muscle
- Vascular endothelial rebuilds endothelial lining by multiplying endothelial cells
Fibrinolysis
Plasma protein trapped in clot- converted Plasmin-digest Fibrin
Thrombosis
Blood clotting (Thrombus) in arteries, veins or capillaries
Embolism
Blood clot/endogenous materials (Embolus) moving in the blood vessel and obstructing blood flow
Liver dysfunction
Clotting factors synthesis
Malnutrition of Vitamin
Hepatitis, Cirrhosis
Impaired Bile production- needed for fat and vit.K absorption
A blood group
- Antigen A on red blood cell
- Antibody B attaches immunoglobin
B blood group
- Antigen B on red blood cell
- Antibody A attaches immunoglobin
AB blood group
- Antigen A and B
- There are no antibodies
O group
- No antigens on red blood cell
- Has both A and B antibodies
Rhesus factor
- Carry Rhesus factor which is antigen D so will be positive
