All animals must have somatic sensations which permit them to sense external environmental stimuli, including chemical, mechanical and electrical inputs so that they would adapt and respond accordingly. Sensation of itch is the least understood among all somatic sensations (pain, touch, temperature, itch, body posture etc).
Scratch is an innate reflex (genetically programmed), and may occur in the absence of the brain. In contrast, itch is a perception originated in the brain. Itch is an unpleasant sensation that evokes the desire to scratch. Scratching response of animals provides a relatively simple behavioral output enabling us to study underlying neural circuits and accompanying signaling mechanisms.
A fundamental question we are interested is how our brain perceives itch as itch, pain as pain. Is the itch signal transmitted through an itch-specific neuronal pathway? What is the molecular basis of itch sensation?
We use the mouse as the model system to address these important questions. Mouse serves the best animal model for elucidating molecular and neuronal mechanisms of itch circuit because this simple reflex can be easily observed, quantified and manipulated by pharmacological, molecular and genetic approaches.
We are using multi-disciplinary approaches including molecular, cellular, biochemical, genetic and electrophysiological approaches to understand neural circuits and signaling mechanisms of itch sensation, as well as their interactions with the skin and immune systems.