Effect of Intravenous Blood Thromboplastin Intermediates on Clotting in Rats

Abstract
Rats were given intravenous injections of blood thromboplastin intermediates. Fully formed blood thromboplastin and product II of Bergsagel and Hougie produced the defibrination syndrome, whereas thromboplastin generation reagents singly or in combination were tolerated without adverse sympatomatic or coagulation effects. In the latter case, there was no evident elevation of blood anticoagulant activity. It is concluded that protection against the intravenous introduction of potential coagulants exceeds that to be accounted for by circulating anticoagulants. A cellular mechanism is hypothesized which clears circulating blood of potential coagulant activity.