FIGURE 9.
Pathways of facilitation of mGlu1/5 receptor‐mediated pain under inflammatory conditions. The increase of TrkA signalling by NGF in inflamed tissue stimulates the expression of TRPV1 channels and its scaffolding protein AKAP5, leading to an increase in AKAP5‐dependent phosphorylation of TRPV1 protein on S800. The stimulation of mGlu1/5 receptors (mGluR1/5) by glutamate and DHPG generates TRPV1‐mediated inward current via the PLC‐DAG pathway to directly excite the nociceptive neurons. The facilitation of mGlu1/5 receptor‐mediated excitation in nociceptive neurons by endogenous glutamate release exacerbates inflammatory pain