Erasing injury-related cortical synaptic potentiation as a new treatment for chronic pain.

Department of Physiology, Faculty of Medicine, Center for the Study of Pain, University of Toronto, Medical Science Building, Room no. 3342, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada.
Journal of Molecular Medicine (Impact Factor: 4.77). 05/2011; 89(9):847-55. DOI: 10.1007/s00109-011-0768-9
Source: PubMed

ABSTRACT Synaptic plasticity in the spinal cord and the cortex is believed to be important for the amplification of painful information in chronic pain conditions. The investigation of molecular mechanism responsible for maintaining injury-related plastic changes, such as through the study of long-term potentiation in these structures, provides potential novel targets for designing new medicine for chronic pain. Recent studies using integrative neurobiological approaches demonstrate that protein kinase M zeta (PKMζ) maintains pain-induced persistent changes in the anterior cingulate cortex (ACC), and inhibiting PKMζ by ζ-pseudosubstrate inhibitory peptide produces analgesic effects in animal models of chronic pain. We propose that targeting PKMζ, or its up- or downstream signaling proteins, in the ACC may provide novel clinical treatment for chronic pain.

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