Abstract
Platelets are crucial to the hemostatic response. Their role in coagulation is well
documented and they have been considered for some time to promote resistance of thrombi
to fibrinolysis. Platelets confer resistance to lysis by promoting clot retraction
of the immediate fibrin network and through release of plasminogen activator inhibitor-1
from their α-granules. However, recent developments in the field indicate that the
role of platelets in fibrinolysis is much more diverse. Indeed, novel studies suggest
that platelets form different subpopulations upon activation that play varied roles
in regulating hemostasis. Likewise the developments in our understanding of thrombus
formation, architecture, and changes in fibrin deposition and composition suggest
that these different subpopulations of platelets may populate distinct areas within
thrombi and potentially dictate the local hemostatic balance in these areas. This
review will discuss the diverse roles of platelets in fibrinolysis and highlight the
recent developments in the field and the contribution of both the intracellular pool
of modulators as well as the membrane surface in regulating these processes.
Keywords
platelets - fibrinolysis - factor XIII - plasminogen - fibrinogen
