Interictal levels of calcitonin gene related peptide in gingival crevicular fluid of chronic migraine patients

Calcitonin gene related peptide (CGRP) is a mediator of neurogenic inflammation playing a major role in the pathogenesis of migraine. Increases in serum CGRP have been detected previously in migraineurs and a return to baseline values regarded as successful treatment. As gingival crevicular fluid is known to originate from the serum, the aim of this study is to measure the CGRP content of gingival crevicular fluid (GCF) in chronic migraine patients and to determine whether there is a correlation between serum and GCF values of CGRP. For this study, 24 female individuals suffering from chronic migraine with aura were age-matched with 15 healthy individuals. Serum and GCF samples were obtained from both groups and enzyme linked immunosorbent assay performed to measure CGRP concentration. The level of CGRP in the serum and GCF of chronic migraine patients was 41 ± 16 pg/mL and 0.25 ± 0.09 pg/μg respectively while in healthy individuals CGRP levels were 29 ± 8 pg/mL and 0.19 ± 0.07 pg/μg. The correlation between CGRP levels of the GCF and serum was 0.88 for migraineurs and 0.81 in the controls. Only a weak positive relationship was observed between age and CGRP levels in both groups. CGRP levels were higher in migraineurs compared with controls both in serum and GCF. Furthermore there is a strong correlation between CGRP levels of the serum and GCF. The results of this study suggest that CGRP levels of GCF have potential diagnostic purposes in patients with chronic migraine.