Robert H. Wilkins

The role of circulating substances in intracranial arterial spasm: I. Serotonin and histamine

DURING THE PAST DECADE, the importance of intracranial arterial spasm occurring in patients with subarachnoid hemorrhage has been stressed in the medical literature.1-9 As a result, the deleterious effects of this common phenomenon, with cerebral ischemia and even infarction. are now widely recognized. lO-I6 The mechanisms of intracranial vascular spasm are still ~nknown,~-~J*17 although circulating substances such as catecholamines and serotonin are among the agents that have been implicated by clinical investigations. For example, spasm of the intracranial arteries has been demonstrated ai-teriographically in a ptient with elevated levels of circulating catecholamines caused by pheochromocytoma.18 Similar spasm also has been related to the prodrome of migraine headache,l20 a type of headache relieved by the serotonin antagonist, methysergide.21 In addition, a more direct implication of serotonin comes from a study in which elevated levels of serotonin were demonstrated in three cases in the hematoma fluid surrounding ruptured intracranial aneurysms that were associated with arterial spasm.22 Measurements have been made of serotonin in the blood and cerebrospinal fluid of patients with traumatic injuries, neoplasms, infections, and various other conditions affecting the nervous system.z2-83 However, very few of these patients had vascular lesions, and the coexistence of arterial spasm was not assessed. In the present study, values of serotonin as well as histamine, another agent known to affect cerebral vascular tone,:

Principles Of Neurosurgery

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