We still have only a poor understanding of how certain nerve cells can signal "heat" and "cold" in the body's somatosensory system. This process of thermal transduction has not been clarified for over 50 years, despite rapid advances in other sensory systems based on modern approaches to membrane physiology. It is particularly interesting to know how thermal stimuli that do not cause pain, but simply thermal sensations, are processed by specialized nerve cells. This work utilizes a recently developed technique with a thermal stimulator sufficiently small to heat a single cell, and a way to monitor and control rapid thermal changes at the small tip of the device to control temperature in a micro-environment. The objective is to identify in thermosensitive cells what the molecular mechanisms are for transduction of innocuous thermal stimuli. Neurophysiological methods of current-clamp and voltage-clamp are used on isolated cells in culture. If this novel approach can identify thermally-sensitive membrane channels, it will be a major advance in understanding temperature sensation at the periphery, and the function of "free" nerve endings that have no specialized receptor organs. This work will have impact on somatosensory physiology, on cellular biophysics, and on neuroscience, and be fundamental to understanding how animals respond to slight thermal changes in their environment.
