Vascular Effects of Antimigraine Drugs: pharmacology of human in vitro models in migraine

Migraine is defined as an idiopathic, paroxysmal neurological disorder with moderate to severe attacks of unilateral, throbbing headache exacerbated by physical activity. The migraine attack is accompanied by associated features such as nausea, vomiting, photophobia and phonophobia (Headache Classification Committee of the International Headache Society, 1988). Since migraine is a common illness, it imposes a tremendous health burden on both patient and society (Solomon & Price, 1997). Prevalence rates of migraine vary geographically and its occurrence is dependent on age (most common from age 25-55 years), gender (three times more common in women than in man) and income (affecting lower socio-economic groups more, see Lipton & Stewart, 1997; Silberstein & Lipton, 1996). In about one third of patients (Rasmussen & Olesen, 1992), an aura may precede the migraine headache within one hour (migraine with aura), consisting of focal neurological (scintillating scotoma), sensory (pins or needle feeling or numbness) and/or motor (weakness or paralysis) symptoms. The majority of patients, however, do not present such symptoms (migraine without aura) (Ferrari, 1998). Migraine attacks per se are not necessarily an abnormal feature, considering that anyone may experience one or two migraine attacks in life. Migraine patients are therefore defined as individuals who have had at least two attacks with aura or at least five attacks without aura. To study migraine scientifically, the International Headache Society (IHS) provided some strict and uniform criteria to determine whether a patient is suffering from migraine (Headache Classification Committee of the International Headache Society, 1988) (see Table 1.1 for migraine with and without aura).