Abstract
An assay method for the level of kallikreinogen in human plasma was described: human plasma was incubated with trypsin at 37°C for 10 minutes, then egg white trypsin inhibitor was added to the incubation mixture to inactivate trypsin, and kallikrein thus produced was estimated by its depressor effect on the rabbit blood pressure.
The present investigation revealed that the plasma kallikreinogen levels in healthy persons ranged from 3.5 to 4.4 Frey units per ml of plasma. Low kalli-kreinogen levels were observed in some patients with hyperthyroidism or hepatitis. In some patients with bronchial asthma or Buerger's disease, rather high levels were, found.
