title: Comparison of CGRP and NO responses in the human peripheral microcirculation of migraine and control subjects.
abstract: Calcitonin gene-related peptide (CGRP) and nitric oxide (NO) are two molecules shown to have a role in migraine pathophysiology. Our objective was to test the hypothesis that migraine subjects are particularly sensitive to these signal molecules. The cutaneous microvascular responses to endothelial and non-endothelial dependent dilators were tested using laser Doppler flowmetry in combination with iontophoresis. The blood flow responses to iontophoretic administration of the endothelium-dependent vasodilator acetylcholine (ACh), or to the endothelium-independent dilators sodium nitroprusside (SNP) and CGRP, and to local warming (44 degrees C) were compared in this controlled trial. The design was that of two arms: patients diagnosed with migraine without aura (n = 9) for >10 years were compared with nine healthy subjects matched for age and gender (seven female and two male, age range 30-60 years). Iontophoretic administration resulted in local vasodilation. ACh induced a relaxation of 1225 +/- 245% (relative to baseline) in controls and 1468 +/- 368% (P > 0.05) in migraine. The responses to SNP were 873 +/- 193% in controls and 1080 +/- 102% (P > 0.05) in migraine subjects. The responses to CGRP were 565 +/- 89% in controls and 746 +/- 675% (P > 0.05) in migraine patients. The responses to local heating which induced maximum dilation did not differ between the groups (1976 +/- 314% for controls and 1432 +/- 226% in migraine; P > 0.05. We conclude that there is no change in the microvascular responsiveness of the subcutaneous microvasculature in migraine.
authors.affiliation: Department of Emergency Medicine, Institute of Clinical Sciences, University Hospital, Lund, Sweden. lars.edvinsson@med.lu.se
authors.forename: M-L
authors.initials: ML
authors.lastname: Edvinsson
authors.forename: L
authors.initials: L
authors.lastname: Edvinsson
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000187:drug effects; D015740:Calcitonin Gene-Related Peptide / Q000008:administration & dosage*; D005260:Female; D006358:Hot Temperature; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000187:drug effects* / Q000503:physiopathology*; D008875:Middle Aged; D008881:Migraine Disorders / Q000503:physiopathology*; D009569:Nitric Oxide / Q000008:administration & dosage*; D012867:Skin / Q000098:blood supply*; D014664:Vasodilation
chemical_list: D009569:Nitric Oxide; D015740:Calcitonin Gene-Related Peptide