Nitric Oxide Modulation of Low‐Frequency Oscillations in Cortical Vessels in FHM – a NIRS Study
Objective.— To investigate changes in spontaneous low‐frequency oscillations (LFO) of cortical vessels in response to the nitric oxide donor GTN by near‐infrared spectroscopy in FHM patients.
Methods.— Twenty‐three FHM patients without known mutations and 9 healthy controls received a continuous intravenous infusion of GTN 0.5 µg/kg/minute over 20 minutes. Using near‐infrared spectroscopy, we recorded oxygenated hemoglobin (oxyHb) LFO amplitude bilateral at the frontal cortex at baseline and 15 minutes and 40 minutes after start of the GTN infusion.
Results.— GTN changed oxyHb LFO amplitude in FHM patients (P = .002), but not in healthy controls (P = .121). Only in FHM patients with coexisting common migraine types did GTN infusion induced changes in LFO amplitudes (P < .001), where post‐hoc analysis revealed an increase in LFO amplitude 15 minutes (P = .003) and 40 (P = .013) minutes after start of infusion compared with baseline. Interestingly, GTN infusion induced no changes in LFO amplitude in patients with a pure FHM phenotype (P = .695).
Conclusion.— FHM patients with a mixed phenotype (coexisting common type of migraine) showed an increase in oxyHb LFO amplitude during GTN infusion, whereas FHM patients with pure phenotype showed no changes. These data suggest possible differences in frontal cortical nitric oxide vascular sensitivity between FHM patients with a mixed phenotype and patients with pure FHM.
Document Type: Research Article
Affiliations: From the Danish Headache Center and Department of Neurology, Glostrup Hospital, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark (H.W. Schytz, J.M. Hansen, D. Phillip, and M. Ashina); Photon Migration Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA (J. Selb and D.A. Boas).
Publication date: July 1, 2012