Summary
Evidence is presented in rats that the liver is involved in clearance from the circulation
of the coagulant intermediate, product I. Although product I injected into the general
circulation failed to elicit the defibrination syndrome, similar injections accompanied
by ligation of the hepatic blood supply were followed by a significant drop in plasma
fibrinogen. Product I was largely inactivated following perfusion through the liver,
but addition of antiheparin drugs to the perfusate prevented this inactivation. No
anticoagulant activity could be demonstrated in perfused material. Perfusion through
the liver of product I precursors demonstrated inactivation of factor IX but no effect
on factors V, VII, VIII, or X.
