Abstract
An apprehension for virus contaminant cannot be completely eliminated from urokinase (plasminogen activator) preparation originated from human urine theoretically. In this experiment the effect of heat-treatment of urokinase at 60°for 10 hr on infectivity of viruses added intentionally to urokinase samples was investigated. (1) Ten kinds of viruses used were completely inactivated within 5 hr of incubation at 60°. (2) Decrease of urokinase activity due to heat-treatment was avoided by adding albumin as a stabilizer.
