FOS and migraine disorder: Increased expression of c-Fos in medullary dorsal horn is believed to be related to central sensitization (10).CGRP is a key factor of migraine as a multifunctional regulatory neuropeptide (11): serum concentrations of CGRP increase during attacks (12) and intravenous infusion of CGRP can cause migraine-like symptoms in migraineurs (13).