title: Effect of CGRP and sumatriptan on the BOLD response in visual cortex.
abstract: To test the hypothesis that calcitonin gene-related peptide (CGRP) modulates brain activity, we investigated the effect of intravenous CGRP on brain activity in response to a visual stimulus. In addition, we examined if possible alteration in brain activity was reversed by the anti-migraine drug sumatriptan. Eighteen healthy volunteers were randomly allocated to receive CGRP infusion (1.5 μg/min for 20 min) or placebo. In vivo activity in the visual cortex was recorded before, during and after infusion and after 6 mg subcutaneous sumatriptan by functional magnetic resonance imaging (3 T). 77% of the participants reported headache after CGRP. We found no changes in brain activity after CGRP (P = 0.12) or after placebo (P = 0.41). Sumatriptan did not affect brain activity after CGRP (P = 0.71) or after placebo (P = 0.98). Systemic CGRP or sumatriptan has no direct effects on the BOLD activity in visual cortex. This suggests that in healthy volunteers both CGRP and sumatriptan may exert their actions outside of the blood-brain barrier.
authors.affiliation: Danish Headache Center and Department of Neurology, Faculty of Health Sciences, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 57, Glostrup, 2600 Copenhagen, Denmark. sohail@dadlnet.dk
authors.forename: Mohammad S
authors.initials: MS
authors.lastname: Asghar
authors.forename: Adam E
authors.initials: AE
authors.lastname: Hansen
authors.forename: Henrik B W
authors.initials: HB
authors.lastname: Larsson
authors.forename: Jes
authors.initials: J
authors.lastname: Olesen
authors.forename: Messoud
authors.initials: M
authors.lastname: Ashina
mesh_terms: D000328:Adult; D015740:Calcitonin Gene-Related Peptide / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007262:Infusions, Intravenous; D007279:Injections, Subcutaneous; D008279:Magnetic Resonance Imaging; D008297:Male; D018170:Sumatriptan / Q000008:administration & dosage*; D014662:Vasoconstrictor Agents / Q000008:administration & dosage*; D014665:Vasodilator Agents / Q000008:administration & dosage*; D014793:Visual Cortex / Q000187:drug effects*; D055815:Young Adult
chemical_list: D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D018170:Sumatriptan; D015740:Calcitonin Gene-Related Peptide