Localization of fibrinolytic activity and inhibition of plasmin in the spinal cord of rat, guinea pig, and rabbit.

Fibrinolytic activity (caused by a plasminogen activator) in the spinal cord was highest in the rat, lowest in the rabbit, and intermediate in the guinea pig; In all species the activity was highest in relation to the pia mater. The central spinal canal was active in the rat and the rabbit, but mostly inactive in the guinea pig. Foci of activity were more numerous in the gray matter than in the white matter corresponding to the greater vascularity of the former. In all species ability to inhibit plasmin was related mainly to the gray matter, with an additional area related to the dura mater. The high fibrinolytic activity of the spinal leptomeninges may play a role in the pathogenesis of hemorrhagic processes related to the spinal cord.