Cerebral Vasospasm Induced by Subarachnoid Blood and Serotonin

Blood, as well as serotonin, injected into the subarachnoid space of the monkey produced extensive contraction of intracerebral arteries. This contraction was associated with slight prolongation of circulation time. Blood caused more severe and more rapid onset of spasm than did serotonin. These findings were noted in the intact animal in which angiographic techniques were used to evaluate the caliber of the intracranial vessels and the circulation time.