Summary
Regulated secretion provides a means by which endothelial cells (EC) can rapidly and
selectively alter the microenvironment of individual vascular beds, and modulate the
interrelated processes of coagulation, fibrinolysis, and inflammation. The rapid release
of high molecular weight multimers of von Willebrand factor (VWF) and surface expression
of P-selectin in response to a wide variety of stimuli have been well documented,
and are the result of exocytosis of Weibel-Palade bodies (WPB). The regulated release
of other EC secretory proteins, including tissue plasminogen activator (tPA), interleukin-8,
endothelin-1, and multimerin, has also been described. New light is being shed on
how secretory proteins are selectively targeted to storage granules in EC, and on
the molecular and cellular events that comprise regulated secretion. Knowledge of
the mechanisms of sorting and secretion from EC storage granules may provide basis
for new strategies for treating inflammatory and coagulation disorders.
Keywords
Endothelial cells - secretion - Weibel-Palade bodies - coagulation - inflammation