Researchers at the University of Edinburgh have identified a way to produce a dramatic natural painkilling effect using small doses of certain “cooling chemicals,” either injected or applied to the skin. Working with rats in an animal model study, they demonstrated that the key to this effect is a recently identified protein – TRPM8 – which is found in nerve cells in the skin and can be activated to mediate the sensation of pain by either cool temperatures or cooling chemicals, such as the active ingredient in mint.
The researchers believe their discovery of a mechanism for making use of the body’s own capacity to suppress pain will produce an improvement over conventional painkillers for the treatment of “neuropathic pain” and arthritis, and “has great potential for relieving the suffering of millions of chronic pain patients.” Neuropathic pain is believed to be generated by the nerves themselves rather than by an external cause that can be removed, as in Fibromyalgia.
The TRPM8 protein is one member of a class of recently identified proteins known to mediate various types of stimuli. Research indicates that other proteins in this class can affect the sensations of touch, temperature, and taste, for example.
The report of this study, “Analgesia Mediated by the TRPM8 Receptor in Chronic Neuropathic Pain,” by Susan Fleetwood-Walker and Rory Mitchell, was published in the August 22 issue of the journal Current Biology. It will be freely available to all readers online at http://www.current-biology.com/