Functional bases for a central serotonergic involvement in classic migraine: a speculative view

The rôle of serotonin (5-HT) in the cerebrovascular bed is the subject of the following review. Cerebral blood vessels are supplied with 5-HT-containing fibres which originate in the raphé nuclei in the brainstem. The activation of this system may result in a constriction of large arteries and a dilatation of arterioles. Intra-arterial administration of 5-HT causes reduction in cerebral blood flow and metabolism provided it bypasses the blood-brain barrier. The findings, marked changes in plasma levels of 5-HT and in cerebral blood flow during a classic migraine attack, are suggestive of an involvement of the 5-HT system.