Calcitonin Gene-Related Peptide and Adrenomedullin Levels During Ictal and Interictal Periods in Patients With Migraine

Abstract

Background Peptides related to calcitonin gene-related peptide (CGRP) have been suggested to have a role in migraine. Adrenomedullin (AM) might be a candidate molecule because it is related to pain pathways in the peripheral and central nervous systems and uses the same receptors as CGRP. Methodology In this study, we examined the serum CGRP and AM levels during unprovoked ictal and interictal periods of 30 migraine patients as well as 25 healthy controls. Another focus of this study was on the association of CGRP and AM levels with clinical features. Results Mean serum AM levels were 15.80 pg/mL (11.91-21.43 pg/mL) in the ictal and 15.85 pg/mL (12.25-19.29 pg/mL) in the interictal periods in the migraine group and 13.36 pg/mL (10.84-17.18 pg/mL) in the control group. Mean serum CGRP levels were 2.93 pg/mL (2.45-3.90 pg/mL) in the ictal and 3.25 pg/mL (2.85-4.67 pg/mL) in the interictal periods in the migraine group and 3.03 pg/mL (2.48- 3.80 pg/mL) in the control group. There were no statistical differences between ictal and/or interictal AM and CGRP levels (p = 0.558 and p = 0.054, respectively) which were also comparable with the results of the control group (p = 0.230, p = 0.295, p = 0.987, p = 0.139, respectively). Ictal serum CGRP and/or AM levels did not correlate with any of the reported clinical features. Conclusions Serum AM and CGRP levels are similar in interictal and unprovoked ictal periods in migraine patients and as well in controls. These results do not indicate that these molecules do not have a role in migraine pathophysiology. Considering the broad mechanisms of action of peptides in the CGRP family, further studies are needed in larger cohorts.