The aim of the present study is to explore the importance of migraine genes on the headache/migraine responses after GTN in FHM-patients and healthy volunteers.

Glyceryl trinitrate (GTN) induces migraine attacks indistinguishable from spontaneous attacks in approximately 80% of migraine sufferers. After systemic administration GTN is transformed to nitric oxide (NO). Treatment of spontaneous migraine attacks with an inhibitor of NO is effective in 60% of patients. These data show that NO is involved in both initiation and maintenance of migraine attack.

The importance of migraine genes is disputed. Evidence from FHM patients with known mutations indicates that migraine pathways in FHM may be different from normal migraine. The aim of the present study is to examine whether this difference also exists in FHM patients without known mutations. The project will improve our understanding of the neurobiology of migraine and stimulate development of new treatment targets.

Inclusion Criteria:

• Diagnosis of familial hemiplegic migraine (IHS-classification criteria)

Exclusion Criteria:

Patients and controls:

• A history of cerebrovascular disease and other CNS- disease
• A history of serious somatic and mental disease
• A history suggesting ischaemic heart disease
• A history of hypo- or hypertension
• Daily intake of medication apart from oral contraceptives
• Abuse of alcohol or medicine (opioid analgesics).
• Pregnant or breastfeeding women.

On the study day:

• No intake of a simple analgesic in the previous 48 hours
• No headache in the previous 48 hours