Development, plasticity and pain processing in sensory neurons and in the spinal dorsal horn.
Research interests in Dr. Koerber's laboratory include several projects designed to investigate the processing of somatosensory information following injury. These studies include examinations of plasticity in the processing of both tactile and pain information. Recent studies have documented compensatory reorganization of spinal networks following peripheral nerve injury and subsequent regeneration. These studies have demonstrated many aspects of synaptic reorganization, including reshaping of cutaneous receptive fields, alterations in synaptic efficacy and the formation of new functional connections between sensory fibers and dorsal horn neurons.
Ongoing experiments in the lab focus on plasticity in both primary sensory neurons and central spinal networks involved in pain pathways. Initial studies have quantitatively compared the properties of normal and post-injury cutaneous nociceptive sensory neurons. Results of these studies demonstrate that specific types of nociceptive sensory neurons demonstrate differing degrees of sensitization commensurate with the type of injury. Parallel studies using genetically-altered animals have assessed the roles specific neurotrophins and/or the GDNF family of growth factors may play in this process. The aims of future studies are to determine how changes in the expression of these growth factors in the skin following injury can lead to changes in afferent fiber sensitivity. Possible mechanisms for this sensitization include modulating the expression of mechanically and thermally sensitive ion channels (e.g. ASIC and TRP channels).
Trainees in Dr. Koerber's laboratory have the opportunity to learn a variety of neurophysiological, neuroanatomical, behavioral, and molecular biological techniques. These techniques allow for a robust examination of the response characteristics of the adult and developing nervous system to injury.
Woodbury, C.J. and Koerber, H.R., Widespread projections from myelinated nociceptors throughout the substantia gelatinosa provide novel insights into neonatal hypersensitivity. J. Neurosci. 23: 601-610, 2003.
Woodbury, C.J., Zwick, M., Wang, S., Lawson, J.J., Caterina, M.J., Koltzenburg, M., Albers, K.M., Koerber,H.R. and Davis, B.M. Nociceptors Lacking TRPV1 and TRPV2 Have Normal Heat Responses. J. Neurosci. 24: 6410-6415, 2004.
Brown, P.B., Lawson, J.J., Brown, A.G., Koerber H.R. and Culberson, J.L. From Innervation Density to Tactile Acuity 2: Embryonic and Adult Pre- and Postsynaptic Somatotopy in the Dorsal Horn. Brain Res. 1055: 36-59, 2005.
Koerber, H.R, Mirnics, K and Lawson, J.J. Synaptic Plasticity in the Adult Spinal Dorsal Horn: The Appearance of New Functional Connections Following Peripheral Nerve Regeneration. Exp. Neurol. 200: 468-479, 2006.
Albers, K.M., Woodbury, C.J., Ritter, A.M., Davis, B.M. and Koerber, H.R. GDNF expression in skin alters the mechanical sensitivity of cutaneous nociceptors. J. Neurosci. 26(11): 2981-2990, 2006.