Umbellulone is an active constituent of the leaves of Umbellularia californica. Umbellulone stimulates the TRPA1 channel in a subset of peptidergic, nociceptive neurons, activating the trigeminovascular system via this mechanism[1].
Umbellulone, from µM to sub-mM concentrations, selectively stimulates transient receptor potential ankyrin 1-expressing HEK293 cells[1].
Umbellulone (50-250 nM/5ul) causes an acute nocioceptive response in a dose-dependent manner in Trpa1+/+ mice[1].Umbellulone (150 µg/kg; intravenous or intranasal) do not affect systemic blood pressure[1].Umbellulone (30-150 μg/kg; i.v.) increases meningeal blood flow in a dose-dependent manner[1].
[1]. Nassini R, et al. The 'headache tree' via umbellulone and TRPA1 activates the trigeminovascular system. Brain. 2012 Feb;135(Pt 2):376-90.