Physiology Flashcards
What is an A blood group?
A Ag on RBC surface & anti-B Ab in plasma
What is a B blood group?
B Ag on RBC surface & anti-A Ab in plasma
What is an AB blood group?
A & B Ag on RBC surface; no Ab’s in plasma
What is the universal receipient of RBC?
AB blood group
What is the universal donor of plasma?
AB blood group
What is an O blood group?
Neither A nor B Ag on RBC surface, both Ab’s in plasma
What is the universal donor of RBC’s?
Type O blood group
What is the universal recipient of plasma?
What happens when Rh- mothers are exposed to fetal Rh+ blood?
Make anti-Rh IgG
What does anti-Rh IgG do in subsequent pregnancies?
Crosses the placenta, causing hemolytic dz of the newborn (erythroblastosis fetalis) in the next fetus taht is Rh+
How can erythroblastosis fetalis be prevented?
Rho (D) immune globulin for mother at first delivery to prevent initial sensitization of Rh- mother to Rh Ag
Which vitamin is a component of Procoagulation?
Vitamin K
Warfarin inhibitis ___ ___.
Epoxide reductase
What doe neonates lack?
Enteric bacteria which produce vitamin K
What is Vitamin K deficiency?
Dec synthesis of factors II, VII, IX, X, protein C, protein S
What carries/protects VIII?
vWF
Antithrombin inhibits activated forms of factors_____.
Factors II, VII, IX, X, XI, XII
Heparin activates ____.
Antithrombin
What does Factor V Leiden mutation produce?
Factor V resistant to inhibition by activated protein C
What is used clinically as a thrombolytic?
What happens during the first step of platelet plug formation?
INJURY
- vWF binds to exposed collagen upon endothelial damage
What happens during the 2nd step of platelet plug formation?
ADHESION
- Platelets bind vWF via GpIb receptor at the site of injury only (specific)
- Platelets release ADP & Ca2+ (necessary for cogulation cascade
- ADP helps platelets adhere to endothelium
What is the 3rd step of platelet plug formation?
ACTIVATION
- ADP binding to receptor induces GpIIb/IIIa expression at platelet surface
What is the 4th step of platelet plug formation?
AGGREGATION
- Fibrinogen binds GbIIb/IIIa receptors & links platelets
- Balance b/w Pro & Anti-aggregation factors
- Temporary plug stops bleeding
What are the Pro-aggregation factors?
- TXA2 (released by platelets)
- Dec BF
- Inc platelet aggregation
What are the Anti-aggregation factors?
- PGI2 & NO (released by endothelial cells)
- Inc BF
- Dec platelet aggregation
What is Thrombogenesis?
Formation of insoluble fibrin mesh
What does Aspirin inhibit?
Cyclooxygenase (TXA2 synthesis)
What do Ticlopidine & clopidogrel inhibit?
ADP-induced expression of GpIIb/IIIa
What does Abciximab inhibit?
GpIIb/IIIa directly
What is deficient in von Willebrand’s dz?
vWF
What is deficient in Bernard-Soulier syndrome?
GpIb
What is deficient in Glanzmann’s thrombasthenia?
GpIIb/IIIa
What doe the Acute-phase reactants in plasma cause?
RBC aggregation therby inc RBC sedimentation rate
(RBC have a higher density than plasma)
Which disorders is ESR inc in?
- Infections
- Autoimmune diseases (SLE, RA, temporal arteritis)
- Malignant neoplasms
- GI dz (ulcerative colitis)
- Pregnancy
Which disorders is ESR dec in?
- Polycythemia
- Sickle cell anemia
- Congestive heart failure
- Microcytosis
- Hypofibrinogenemia
