One third of migraine patients experience aura, i.e. dramatic, transient neurological
symptoms, most often in the form of visual disturbances, that usually appear before the onset
of migraine headache. The likely underlying mechanism of aura is known as cortical spreading
depression, a wave of changes in electrical activity that slowly spreads in the outermost
layer of the brain. It is currently not known what causes the aura to initiate in patients or
what the relationship is between aura and migraine headache, e.g. if treatment targeted at
aura mechanisms will prevent subsequent headache. Due to the short-lasting and unpredictable
nature of aura, the only possible approach for systematic investigations is to experimentally
trigger aura, but currently no method for aura-triggering is available.
The overall goal of the proposed project is to reveal the earliest mechanisms of the migraine
attack by investigating the initiating factors of aura in the migraine brain.
Current animal evidence indicates that infusion of endothelin-1 (ET-1), a naturally occurring
signaling molecule released from blood vessels, is safe and very likely to trigger migraine
aura in patients.
In this project the investigators aim to study the effects of ET-1 on the human brain, to
investigate aura-inducing effects of ET-1 in patients and to develop a safe and reliable
method for the experimental induction of migraine aura using ET-1.