Evidence of fibrinogen degradation in rat anaphylaxis.

In active anaphylactic shock of rats pretreated with Bordetella pertussis vaccine, both plasma thrombin clotting time and the amount of antigenically active fibrinogen degradation products in the serum were increased. The formation of clottable fibrinogen fragments was shown by SDS polyacrylamide gel electrophoresis of thrombin-induced clots. When plasma of rats pretreated with 125I rat fibrinogen and then subjected to anaphylaxis was submitted to SDS polyacrylamide gel electrophoresis, fibrinogen-split products were also detected. Fibrinogen degradation results from the proteolytic effect of an activated fibrinolytic enzyme.