Genetic Dissection of Spinal Circuits Processing Mechanical Itch

Abstract

We have all experienced an itch. It is a modality of somatic sensation defined as an unpleasant sensation associated with the desire to scratch. Itch can be evoked in the skin directly by physical stimuli, such as gentle touch, referred as mechanical itch, or by chemical mediators, such as histamine, referred as chemical itch. Mechanical itch was first described in healthy human subjects by Edward Titchener in 1909 that itch points were found in the skin by punctate stimulation with a fine hair. Under pathological conditions, mechanical itch is one of the common symptoms of most patients with chronic itch. In last decades, the neural circuits that transmit chemical itch have been well studied. The neural circuits processing mechanical itch, however, remain still unknown. My lab uses a combination of intersectional genetic manipulations, electrophysiology and behavior analyses to identify the key components of the spinal circuitry for mechanical itch in mice.