Platelet
Aggregating Agonists - 4
Produces platelet agglutination
Ristocetin:
vWf must be present in specimen for platelets to agglutinate
Agglutination diminished in:
70% of von Willebrand
disease (all except subtype 2b)
Bernard-Soulier
syndrome
Does not induce shape change and
only slight secretion
of platelets
Does not produce a primary wave of
aggregation
Gp Ib missing
(collagen receptor)