Dr Brian Cairns, professor in the Faculty of Pharmaceutical Sciences at UBC, studies chronic pain above the neck—migraines and temporomandibular disorders, which cause soreness in the jaw—and is tracking intriguing leads in his search for pain relief. These jaw disorders affect about 10% of people at some point in their life and the pain can be so intense that it becomes difficult to speak or eat. Recently Dr Cairns stumbled across a clue to what might be causing this discomfort.

Glutamate is a neurotransmitter that sends signals between nerve and brain cells. It occurs naturally in the brain and body but may also be consumed in food (monosodium glutamate). The average fast-food meal contains 12 grams of glutamate. Dr Cairns heard about research showing that glutamate activates receptors in the brain, and he knew these receptors are also found around the eyes and in skin and muscles, and, when activated, cause pain. His research led him to wonder if eating glutamate caused pain and he asked young, healthy people to ingest 12 grams of the amino acid and watched what happened. The experiment induced headaches, nausea, or jaw pain about 50% to 60% of the time.

He also convinced patients with temporomandibular disorders to let his team stick a needle through their cheeks to measure glutamate levels in their jaw muscles and found higher levels of glutamate where the muscles were most painful.

Dr Cairns suspects if glutamate levels spike in an area around the nerves in the head it triggers headaches, such as migraines, so his idea is to develop a drug that reduces glutamate levels in this area. For more information on the research Dr Cairns is involved in, visit www.pharmacy.ubc.ca/research/researchers/brian-cairns [8].