Proteolysis of fibrinogen in healthy volunteers following major and minor vivo plasminogen activation.

Changes in immunoreactive fibrinopeptide A, fragment B beta 1-42 and fragment E were followed after major and minor in vivo plasminogen activation, after infusion of streptokinase and acylated streptokinase-plasminogen complex respectively, in healthy male volunteers. Major activation resulted in a dramatic rise in all three peptides, fragment E persisting in the circulation longest. Fragment B beta 1-42 was also markedly increased after minor systemic plasminogen activation despite apparently adequate levels of immediate antiplasmin.