Fibrinolytic activity in the inner ear of human beings and guinea pigs.

Fibrinolytic activity in the inner ear of human beings and guinea pigs was assayed qualitatively and quantitatively. It was found that fibrinolytic activity of the stria vascularis was caused by a conversion of plasminogen to plasmin by tissue plasminogen activator and was moderate in degree compared with that of other organs in both species. In human beings, endolymph showed higher plasminogen activator activity than that of CSF. Plasminogen activator activity was not detected in either endolymph or perilymph of guinea pigs. Thrombin infusion diminished plasminogen activator activity in the stria vascularis of guinea pigs.