TRPA1 and migraine disorder: Umbellulone, the primary component of Umbellularia californica (California bay laurel) and a TRPA1 agonist (able to induce nociceptive behavior, nasal mucosa vasodilation, and the release of CGRP from meningeal tissue in rats), has been found to trigger migraine-like and cluster-like headaches in susceptible individuals [163].