tPA neurotoxic

Tissue plasminogen activator (tPA) has been found to dissolve blood clots effectively, an activity useful both in treating heart attack and stroke. However, in humans the effects of tPA in stroke cannot be studied apart from the drug's thrombolytic effects. Harvard researchers have now examined the effects of tPA separately from its cardiovascular properties by inducing strokes in mice through occlusion of the middle cerebral artery.

In Nature Medicine, they reported that infarct size, the region of ischemic damage that follows a stroke, was reduced by 50 percent in mice that lack tPA genetically, and that intravenous administration of tPA increased infarct size in both normal and tPA-deficient mice...