Capsaicin failed in suppressing cortical processing of CO2 laser pain in migraine patients.

Abstract

The aim of this study was to compare the properties of the nociceptive system in eight migraine without aura patients in the pain-free phase with 10 healthy controls, by evaluating the topography and the source of the CO2 laser-evoked potentials (LEPs) obtained by the right supraorbital skin, during and after capsaicin topical application. In healthy subjects the acute cutaneous pain induced by capsaicin reduced the amplitude of the vertex LEPs and induced a posterior shifting of the P2 wave dipolar source within the anterior cingulate cortex. These functional changes seemed significantly reduced in migraine patients, for a disturbed pattern of pain modulation at the cortical level, which may subtend the onset and persistence of migraine.

• Authors: Marina de Tommaso, Luciana Losito, Olimpia Difruscolo, Michele Sardaro, Giuseppe Libro, Marco Guido, Paolo Lamberti, Paolo Livrea
• Journal: Neuroscience letters (Neurosci Lett) 2005 Aug 12-19 Vol. 384 Issue 1-2 Pg. 150-5 ISSN: 0304-3940 [Print] Ireland
• PMID: 15927376 (Publication Type: Clinical Trial, Comparative Study, Journal Article)

Chemical References

• Capsaicin

Topics

• Adult
• Analysis of Variance
• Brain Mapping
• Capsaicin (pharmacology)
• Case-Control Studies
• Electroencephalography (methods)
• Evoked Potentials, Somatosensory (physiology)
• Female
• Humans
• Magnetic Resonance Imaging (methods)
• Male
• Migraine Disorders (pathology, physiopathology)
• Pain Measurement (methods)
• Pain Threshold (drug effects)
• Reaction Time (drug effects, physiology)
• Skin (innervation, physiopathology)