Topic 14: PRP Flashcards
Young, fecund, robust, inactivated platelets are what size?
1-3 μm discoids
Humans: Normally ~ platelet count?
150,000-300,000/ml of blood
platelets life span?
1 week
α-granules contain? (in platelets)
clotting factors, growth factors, and various other proteins
Dense granules contain? (in platelets)
ADP, ATP, Serotonin, and Calcium
Young compared to old platelets size?
Young platelets are large and heavy (dense)
Old platelets are small and light
Young compared to old platelets aggregation?
Young large platelets aggregate much faster (3-5 x) than older platelets
Young compared to old platelets ATP and ADP?
Young platelets release dramatically more ATP (4-8 x) and ADP (4-6 x) than do older platelets
Old platelets to be activated?
Old platelets require substantially greater amounts of ADP to be activated than do young platelets
Wound –>
Exposes subendothelial collagen –>
_____?_____ –>
Platelet adhesion to blood vessel wall via glycoprotein IIb/IIIa receptors –>
Platelet activation –>
Platelet cytoskeleton (via actin and myosin) expands from a disc to a multi-pseudopodal sticky blob –>
Platelet aggregation –>
Serotonin –> ______ –>
ADP –> Recruits other platelets to aggregate and ____ –>
Thromboxane –> Platelet aggregation and PGF release
…and more cytokines, chemotactic and growth factors, etc., etc. than you can imagine (more are discovered on a monthly basis)
Binds von Willebrand Factor
Vasoconstriction
degranulate
Wound –>
Exposes _____ –>
Binds von Willebrand Factor –>
Platelet adhesion to blood vessel wall via ________ –>
Platelet activation –>
Platelet cytoskeleton (via actin and myosin) expands from a disc to a multi-pseudopodal sticky blob –>
Platelet aggregation –>
Serotonin–> Vasoconstriction –>
___ –> Recruits other platelets to aggregate and degranulate –>
______ –> Platelet aggregation and PGF release
…and more cytokines, chemotactic and growth factors, etc., etc. than you can imagine (more are discovered on a monthly basis)
subendothelial collagen
glycoprotein IIb/IIIa receptors
ADP
Thromboxane
Serotonin
Vasoconstriction
ADP
Recruits other platelets to aggregate and degranulate
Thromboxane
Platelet aggregation and PGF release
PDGF: Platelet-Derived Growth Factor - does what??
STRONGLY mitogenic and chemotactic for leukocytes
By itself PDGF application doubles the rate of collagen deposition in a wound
(plus a bunch of other stuff that aggressively accelerates healing…)
PDGF doubles what?
By itself PDGF application doubles the rate of collagen deposition in a wound
TGF-β: Transforming Growth Factor-Beta
Also strongly mitogenic Allows damaged (irradiated, corticosteroid-treated) tissues to revert to normalized collagen deposition
Attracted neutrophils and macrophages release ?
a host of other healing factors