Evidence for increased plasma levels of calcitonin gene-related peptide inmigraine outside of attacks

Although calcitonin gene-related peptide (CGRP) has been shown to be elevat ed in jugular venous blood of adult migraineurs during acute migraine attac ks, it remains unknown whether CGRP is increased outside of attacks in jugu lar or cubital venous blood. The aim of the present study was to compare in terictal plasma levels of CGRP in adult migraine patients and in healthy co ntrols. Twenty patients with a diagnosis of migraine with or without aura a nd 20 healthy controls were included. In blood from the cubital vein, CGRP levels were significantly higher in patients (75 +/- 8 pmol/l (mean +/- SEM )) than in controls (49 +/- 3 pmol/l) (P = 0.005). The subgroup of patients suffering exclusively from migraine without aura (n = 14) also had signifi cantly higher levels of CGRP (82 +/- 10 pmol/l) than controls (n = 20; 49 /- 3 pmol/l) (P = 0.001), The findings could not be explained by confoundin g factors such as age, sex or use of contraceptive pills. We therefore conc lude that CGRP is increased in cubital venous blood of migraineurs outside of attack. It is hypothesized that this finding may reflect a long-lasting or permanent abnormal neurogenic vascular control in patients with migraine . (C) 2000 International Association for the Study of Pain. Published by El sevier Science B.V. All rights reserved.