The roles of neuropeptides
Electrical stimulation of the trigeminal ganglion and superior sagittal sinus induces sterile neurogenic inflammation of the dura mater, i.e. without associated pathogenic microorganisms, with vasodilation, plasma protein extravasation, mast cell degranulation and platelet aggregation (Burstein et al. 2010; Goadsby et al. 2017). The extra-cerebral blood volume increases and neuropeptides, with strong vasodilating power, are released. There is thus an increase in the peptide related to the calcitonin gene (CGRP) in the jugular veins, in substance P, in the activating polypeptide of pituitary adenylate cyclase (PACAP) and in vasoactive intestinal peptide (VIP).