Here, we review the role of pituitary adenylate cyclase-activating peptide-38 (PACAP38) in migraine and cluster headache¬†(CH). Mounting evidence implicates signaling molecule PACAP38 in the pathophysiology of migraine. Human provocation¬†studies show PACAP38 induces migraine attacks in migraine patients without aura and marked and sustained dilation of¬†extracerebral arteries. Read More →