Patients with migraine, without aura (MO), either during or between attacks, present elevated histamine levels in platelet-poor plasma but normal whole blood histamine levels, compared with controls. This finding is usually interpreted as an increased histamine release from basophils due to unidentified histamine-releasing factors. Compared with 10 control plasma samples, each sample from 12 MO patients (5 during and 7 between in attacks) contained normal amounts of iron and immunologically reactive transferrin but decreased transferrin iron-binding capacity. As transferrin inhibits histamine release in vitro, such as functional abnormality, probably due to modifications of the transferrin glycan moiety (desialylated transferrin), may well account for the increased histamine release observed in MO patients. We suggest that glycan-modified transferrin may be related to migraine histamine-releasing factors.
Read full abstract