Supersensitivity of brachial artery endothelium-independent vasodilatation reverses to a normal response to flunarizine in subjects with migraine

Background: We investigated the effects of arterial supersensitivity in the intracranial and peripheral arteries, and the effects of flunarizine on nitroglycerin (NTG)-mediated vasodilatation of the brachial artery (BA). Methods: We assessed BA function in 12 patients with migraine and in 11 age-matched controls. We measured flow-mediated vasodilatation (FMD) and NTG-mediated vasodilatation by high-resolution ultrasound. We used the Migraine Disability Assessment (MIDAS) Questionnaire to classify migraines and a headache score (HA score) on a scale from 0 to 10 to define the intensity of NTG-induced headaches. All measures were re-checked after treatment with flunarizine (10 mg per os at bedtime) for three months. Results: The MIDAS score of the migraine group improved from 59.5 ± 15.0 to 10.4±3.5 and the HA score of NTG-induced headaches improved from 6.3 ± 0.4 to 1.3 ± 0.6 in the migraine group. However, there were no differences in either score in the control group. Arterial supersensitivity of BA to NTG was also noted in the migraine group, but disappeared after flunarizine treatment. Vasodilatation was 24.7 ± 2.4% in the migraine group versus 14.7 ± 2.4% in the control group. Vasodilatation reduced to 12.8 ± 1.6% in the migraine group. Conclusions: Flunarizine exhibits prophylactic effects on migraine and NTG-induced headache. This is the first report to show that NTG-induced headaches can be successfully prevented by flunarizine. Migraine sufferers also showed arterial supersensitivity of BA to NTG, which could be reversed by flunarizine.