Coagulopoietin activity in rat plasma: influence of degree of hypoprothrombinemia and reproducibility of the response.

Injection of plasma from a vitamin K-deficient hypoprothrombinemic rat into a normal rat causes an increase in plasma prothrombin activity in the recipient rat. Maximum concentrations of the factor responsible for this response (coagulopoietin) are present in the plasma of rats fed a vitamin K-deficient diet for 7 days and do not increase as the period of deficiency is increased. The coagulopoietin activity of plasma from individual rats is variable, but similar activity was observed when multiple recipient rats received the same donor plasma.