Physiopathology of migraine

: The basic theories on the origin of migraine are reviewed. A vascular paroxysm was the initial hypothesis, followed by the "spreading depression" phenomenon based of regional flow studies of Danish authors. A third hypothesis relates the origin of migraine to liberation of substance "p" and others (K, neurotransmitters and polypeptides) from trigeminal nerve endings. Finally, a behavioral disturbance originating an adrenergic response and a loss of central nervous system defense mechanisms, has been also postulated.