VISCERAL PAIN THRESHOLD IS DEEPLY LOWERED FAR FROM THE HEAD IN MIGRAINE

A short lasting over-distension of the hand-forearm veins, obtained th rough a non-invasive original maneuver (Hand Arm Vein Distension test) induces local pain when applied to migraine sufferers in inter-critic al period. Conversely, subjects with an absolutely negative personal a nd family history for any type of idiopathic headache do not report an y pain or only an uncertain, slight one.The injection of 1 mt of 2% to 8% (i.e. 0.34 mol/L to 1.36 mol/L) hypertonic saline into the antecub ital vein during an extemporary short (1 minute) circulatory blockage (ischemia induced to guarantee a strictly local action of the chemical stimulus) provokes moderate, strong or unbearable local (arm vein) pa in in migraine sufferers but not in subjects with a personal and famil y history absolutely free from any type of headache. These results sho w for the first time that migraineurs show a proneness to visceral pai n in viscera (veins) distant from the head (arm-hand). Such a finding is consistent with the theory that migraine pain is due to a central d erangement of the viscerosensory system.