thrombogen

The conversion of thrombogen into prothrombin has been proved to be due to the action of a second ferment which has been named thrombokinase, and this latter is again absent from living blood.

Hence the question arises, whence are derived thrombogen and thrombokinase?

The plasma collected from such blood is found to contain thrombogen but no thrombokinase.

A somewhat similar plasma may be prepared from a mammal’s blood by collecting samples of blood from an artery into vessels which have been thoroughly coated with paraffin, though in this instance thrombogen may be absent as well as thrombokinase.

If plasma containing thrombogen but no thrombokinase be treated with a saline extract of any tissues it will soon clot.