Chilli-like chemical part of the pain pathway
A group of substances similar to those that give chillies their kick are part of the body's pain mechanism, research on mice has shown.
Scientists have found that the body releases a chemical called OLAM (oxidized linoleic acid metabolite) when injured. Surprisingly, OLAM resembles capsaicin: the naturally occurring ingredient in chillies which is known to cause their ‘burning sensation'. Capsaicin binds with a special type of receptor to activate the pain mechanism. Researchers wanted to find out how these receptors were activated when the body is injured.
To find out, they took skin cells and neurons from mice and grew some of them with their pain receptors and some without. They then exposed the cells to water with temperatures of 43 degrees Celsius, which is the threshold after which a human would begin to feel discomfort. The cells with the receptors developed and released OLAM, which bound to the receptors and initiated the pain sequence.
The results point to a previously unrecognised series of chemicals involved in triggering the pain sensation. Drugs could be developed which either inhibit or stop the creation of OLAM, leading to potential new treatments for the millions of people affected by chronic pain caused by disease or injury.