Francesca Cangi

The pressor hyperresponsiveness to phenylephrine unmasks sympathetic hypofunction in migraine

The pressor responsiveness to phenylephrine, an almost pure agonist of peripheral alpha-1-adrenoceptors, was studied in 32 migraine patients in headache-free intervals. Eighteen healthy volunteers served as a control group. Fourteen patients and 14 controls also underwent the tilt test. The following observations were made: (1) the pressor response to phenylephrine was significantly greater and longer lasting in patients than in controls; (2) the reflex decrease of heart rate did not differ in the two groups; (3) a normal orthostatic increase of blood pressure and heart rate occurred in migraineurs with hyperresponsiveness to phenylephrine. These findings suggest a supersensitivity of vascular adrenoceptors which is compatible with a chronic adrenergic deficiency in migraineurs. Since patients did not show an orthostatic hypotension in attack-free periods, the compensatory character of receptoral supersensitivity and the possible mechanisms of cardiovascular dysautonomia, which may occur during migraineous attack, were discussed.

Emergence of Pain and Extra-Pain Phenomena from Dopaminomimetics in Migraine

During migraine attacks clinical signs that could be attributed to peripheral and central dopamine (DA) involvement such as yawning, nausea, vomiting, drowsiness, circulatory collapse, shivering, and perceptive distortion are often present.

Pentazocine in Migraine: Subjective and Pupillary Abnormal Effects

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