The serotonergic system in migraine

Serotonin (5–HT) and serotonin receptors play an important role in migraine pathophysiology. Changes in platelet 5–HT content are not casually related, but they may reflect similar changes at a neuronal level. Seven different classes of serotoninergic receptors are known, nevertheless only 5–HT(2B–2C) and 5HT(1B–1D) are related to migraine syndrome. Pharmacological evidences suggest that migraine is due to an hypersensitivity of 5–HT(2B–2C) receptors. m–Chlorophenylpiperazine (mCPP), a 5–HT(2B–2C) agonist, may induce migraine attacks. Moreover different pharmacological preventive therapies (pizotifen, cyproheptadine and methysergide) are antagonist of the same receptor class. On the other side the activation of 5–HT(1B–1D) receptors (triptans and ergotamines) induce a vasocostriction, a block of neurogenic inflammation and pain transmission.