Fibrinolytic activity evoked in the plasma of the normal and adrenalectomized rat by cellulose sulphate.

1. Cellulose sulphate, a kinin-releasing agent, produced fibrinolytic activity in plasma when administered intravenously to the rat but not when added to fresh rat plasma in vitro. The in vivo effect was maximal within 1 min and disappeared within 10-20 minutes. It was retained in plasma taken 1 min after the injection and kept at room temperature for 30 minutes.2. A decrease of anti-fibrinolytic potency measured against urokinase-activated bovine plasmin, was shown to occur in plasma of rats given cellulose sulphate.3. Activated rat plasma lysed heat-denatured fibrin: it probably contains free plasmin as well as plasminogen activator.4. Adrenalectomized rats did not exhibit fibrinolytic activity nor statistically significant benzoyl-arginine ethyl ester-esterase activation in plasma after cellulose sulphate treatment.5. Adrenalectomized rats had significantly increased levels of plasma kininogen, but were normally sensitive to the kininogen-depleting action of cellulose sulphate.6. The increased plasma kininogen of adrenalectomized rats seems to be a consequence of the impairment of the plasminogen activating mechanism.