||Neuropathic pain is one of the chronic pain that causes severe disturbance to quality of life.|
Inflammation accompanied with the nerve injury is associated with induction of neuropathic
pain. While inflammation happened, cytokines release and induce immune cells recruitment.
Furthermore, the local tissue acidosis accompanied with the nerve injury also plays an
important role in neuropathic pain. Ovarian Cancer G Protein-Coupled Receptor 1 (OGR1),
a proton-sensing GPCR fully activated at pH6.8 environment is expressed in small-diameter
dorsal root ganglion (DRG) neurons, macrophages and lymphocytes. Cytokines increase
OGR1 expression in immune cells to regulate the function of immune cells. However, it
remains unclear which role OGR1 plays in neuropathic pain. To address these questions,
used shRNA to knockdown OGR1 gene expression in peripheral afferents before chronic
constriction injury (CCI) of the sciatic nerve. Knockdown of OGR1 gene expression
reversed CCI-induced mechanical hyperalgesia from 4 weeks to 14weeks post CCI surgery.
Intracellular calcium signals recorded in DRG neurons were upregulated post CCI surgery,
and further increased at least 4w. Suppression of OGR1 gene expression inhibited calcium
signals at 4w after CCI, maining in IB4(-) neurons. Accordingly, these results suggested that
OGR1 may regulate intracellular calcium signals in neuron to reverse CCI-induced
||M.(2001) The LANSS Pain Scale: the Leeds assessment of neuropathic symptoms|
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