Platelet serotonin metabolism and ultrastructure in migraine.

Biochemical and ultrastructural techniques were used to study the nature of platelet serotonin involvement in migraine. Serotonin levels were increased to a moderate degree in classic migraine, but not in common migraine. The platelet content of 5-hydroxyindoleacetic acid was equally reduced in both classic and common migraine. Platelet-dense bodies, the storage organelles for serotonin, were increased in both migraine groups, particularly in classic migraine. The results were interpreted as evidence for reduced platelet serotonin turnover combined with dense body hyposecretion in migraine sufferers. These findings are further supportive evidence for altered serotonergic function between attacks of migraine, and argue in favor of a role for serotonin in the mechanisms of a migraine attack.