Anesthesiology; Nervous System; Neurochemistry; Neurons; Neurophysiology; Pain; Electrophysiological Processes; Nociceptive Pain
Our research focuses on the neural mechanisms of pain and itch. Experiments on pain examine the functional properties of dorsal root ganglion (DRG) neurons in the rodent. We are currently interested in how electrophysiological and neurochemical changes in these properties, occurring after a chronic compression of the DRG (CCD model), lead to behavioral signs of neuropathic pain. This type of pain might be produced in humans after injuries and degenerative disorders of the spine. Our experiments on itch use psychophysical methods in humans and behavioral testing in animals to measure itch and nociceptive sensations that can occur under normal conditions and after inflammatory or neuropathic disorders affecting the skin.
In our animal models, the neural encoding of normal and pathological itch vs. pain is measured using imaging and electrophysiological recordings of visualized sensory neurons in vitro and in vivo. Transgenic mice are used that express a fluorescent marker in a subset of itch or pain mediating DRG neuron to facilitate identification for functional studies. A major goal is to identify neurons and neurochemical mechanisms that could be targeted in clinical treatments of chronic pruritus or pain.
Specialized Terms: Pain; Dorsal root ganglion; Neurons; Electrophysiological; Neurochemical; Itch; Psychophysical; pruritic; Nociceptive sensations; Anesthesiology; Electrophysiology; Nervous System; Neurophysiology; Sensory System
- Psychophysical Measurements of Itch and Nociceptive Sensations in an Experimental Model of Allergic Contact Dermatitis. Pall PS, Hurwitz OE, King BA, LaMotte RH. J Pain 16(8):741-749
- CXCR3 chemokine receptor signaling mediates itch in experimental allergic contact dermatitis. Qu L, Fu K, Yang J, Shimada SG, LaMotte RH. Pain 156(9):1737-1746
- Enhanced excitability of MrgprA3-positive and MrgprD-positive nociceptors in a model of inflammatory itch and pain Qu L, Fan N, Ma C, Wang T, Han L, Fu K, Wang Y, Shimada SG, Dong X, LaMotte RH. Brain 137(Pt 4):1039-1050
- Han, L., Ma, C., Liu, Q., Weng, H.J., Cui, Y., Tang, Z., Kim, Y., Nie, H., Qu, L., Patel, K.N., Li, Z., McNeil, B., He, S., Guan, Y., Xiao, B., LaMotte, R.H. & Dong, X. (2012). A subpopulation of nociceptors specifically linked to itch. Nature Neuroscience 16(2), 174-182. PMCID: PMC3557753
- Ma C, Nie H, Gu Q, Sikand P, LaMotte RH. In-vivo responses of cutaneous C-mechanosensitive neurons in mouse to punctate chemical stimuli that elicit itch and nociceptive sensations in humans. J. Neurophysiol 107(1):357-63, 2012.
- Shimada SG and LaMotte RH (2008) Behavioral differentiation between itch and pain in mouse, Pain, 139, 681, Published