Intravenous delivery of a PAC1 receptor antagonist specifically inhibited the meningeal vasodilatory effects of dural trigeminovascular activation, whereas only central (intracerebroventricular) administration of the drug inhibited dural nociceptive‐evoked action potentials in central trigeminovascular neurons, suggesting that a central role of PACAP in migraine is likely in addition to the primary afferent innervation in the meninges.99 This evidence concerns the gene ADCYAP1 and migraine disorder.