One whiff of a plant known as the headache tree can spur intense, excruciating pain — and now scientists know why. An ingredient in the tree sets off a chain of events that eventually amps up blood flow to the brain’s outer membrane.
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Other headache triggers, such as chlorine, cigarette smoke and formaldehyde, interact with some of the same cellular machinery, suggesting they all work via the same pain-inducing mechanism.
In the new study, an international group of researchers extracted the plant compound umbellulone from dried bay laurel leaves and then exposed various mouse and rat cells to the compound. Umbellulone tickles the same cellular detector that responds to painfully cold stimuli and the sinus-clearing scent of wasabi and mustard oil, the researchers report online October 27 in Brain.